Remove unneeded uses of setimmediatevalue()

Up until
cocotb/cocotb@bfd811b
setimmediatevalue() did not actually work as expected. Using regular
value assignment preserves the old behavior.

src/cocotb_bus/drivers/amba.py

@@ -71,12 +71,12 @@ def __init__(self, entity: SimHandleBase, name: str, clock: SimHandleBase,
                  **kwargs: Any):
         BusDriver.__init__(self, entity, name, clock, **kwargs)
 
-        # Drive some sensible defaults (setimmediatevalue to avoid x asserts)
-        self.bus.AWVALID.setimmediatevalue(0)
-        self.bus.WVALID.setimmediatevalue(0)
-        self.bus.ARVALID.setimmediatevalue(0)
-        self.bus.BREADY.setimmediatevalue(1)
-        self.bus.RREADY.setimmediatevalue(1)
+        # Drive some sensible defaults
+        self.bus.AWVALID.value = 0
+        self.bus.WVALID.value = 0
+        self.bus.ARVALID.value = 0
+        self.bus.BREADY.value = 1
+        self.bus.RREADY.value = 1
 
         # Set the default value (0) for the unsupported signals, which
         # translate to:
@@ -91,7 +91,7 @@ def __init__(self, entity: SimHandleBase, name: str, clock: SimHandleBase,
             "ARID", "ARREGION", "ARLOCK", "ARCACHE", "ARPROT", "ARQOS"]
         for signal in unsupported_signals:
             try:
-                getattr(self.bus, signal).setimmediatevalue(0)
+                getattr(self.bus, signal).value = 0
             except AttributeError:
                 pass
 
@@ -596,10 +596,10 @@ def __init__(self, entity, name, clock, memory, callback=None, event=None,
         self.clock = clock
 
         self.big_endian = big_endian
-        self.bus.ARREADY.setimmediatevalue(1)
-        self.bus.RVALID.setimmediatevalue(0)
-        self.bus.RLAST.setimmediatevalue(0)
-        self.bus.AWREADY.setimmediatevalue(1)
+        self.bus.ARREADY.value = 1
+        self.bus.RVALID.value = 0
+        self.bus.RLAST.value = 0
+        self.bus.AWREADY.value = 1
         self._memory = memory
 
         self.write_address_busy = Lock("%s_wabusy" % name)

src/cocotb_bus/drivers/avalon.py

@@ -49,25 +49,25 @@ def __init__(self, entity, name, clock, **kwargs):
         self._can_read = False
         self._can_write = False
 
-        # Drive some sensible defaults (setimmediatevalue to avoid x asserts)
+        # Drive some sensible defaults
         if hasattr(self.bus, "read"):
-            self.bus.read.setimmediatevalue(0)
+            self.bus.read.value = 0
             self._can_read = True
 
         if hasattr(self.bus, "write"):
-            self.bus.write.setimmediatevalue(0)
+            self.bus.write.value = 0
             self.bus.writedata.value = create_binary_from_other(self.bus.writedata.value,
                                                                 "x" * len(self.bus.writedata))
             self._can_write = True
 
         if hasattr(self.bus, "byteenable"):
-            self.bus.byteenable.setimmediatevalue(0)
+            self.bus.byteenable.value = 0
 
         if hasattr(self.bus, "cs"):
-            self.bus.cs.setimmediatevalue(0)
+            self.bus.cs.value = 0
 
-        self.bus.address.setimmediatevalue(create_binary_from_other(self.bus.address.value,
-                                                                    "x" * len(self.bus.address)))
+        self.bus.address.value = create_binary_from_other(self.bus.address.value,
+                                                          "x" * len(self.bus.address))
 
     def read(self, address):
         pass
@@ -260,10 +260,10 @@ def __init__(self, entity, name, clock, readlatency_min=1,
         self._coro = cocotb.start_soon(self._respond())
 
         if hasattr(self.bus, "readdatavalid"):
-            self.bus.readdatavalid.setimmediatevalue(0)
+            self.bus.readdatavalid.value = 0
 
         if hasattr(self.bus, "waitrequest"):
-            self.bus.waitrequest.setimmediatevalue(0)
+            self.bus.waitrequest.value = 0
 
         if hasattr(self.bus, "burstcount"):
             if hasattr(self.bus, "readdatavalid"):
@@ -275,7 +275,7 @@ def __init__(self, entity, name, clock, readlatency_min=1,
                 self.bus.waitrequest.value = 0
 
         if hasattr(self.bus, "readdatavalid"):
-            self.bus.readdatavalid.setimmediatevalue(0)
+            self.bus.readdatavalid.value = 0
 
     def _pad(self):
         """Pad response queue up to read latency."""

src/cocotb_bus/drivers/opb.py

@@ -28,7 +28,7 @@ class OPBMaster(BusDriver):
 
     def __init__(self, entity, name, clock, **kwargs):
         BusDriver.__init__(self, entity, name, clock, **kwargs)
-        self.bus.select.setimmediatevalue(0)
+        self.bus.select.value = 0
         self.log.debug("OPBMaster created")
 
     @coroutine