Fixed cast_lossless clippy warnings

Author: ZapAnton

vm/src/stdlib/os.rs

@@ -18,7 +18,7 @@ use super::super::vm::VirtualMachine;
 pub fn raw_file_number(handle: File) -> i64 {
     use std::os::unix::io::IntoRawFd;
 
-    handle.into_raw_fd() as i64
+    i64::from(handle.into_raw_fd())
 }
 
 #[cfg(target_family = "unix")]

vm/src/stdlib/pystruct.rs

@@ -287,7 +287,7 @@ fn unpack_u64(vm: &mut VirtualMachine, rdr: &mut Read) -> PyResult {
 fn unpack_f32(vm: &mut VirtualMachine, rdr: &mut Read) -> PyResult {
     match rdr.read_f32::<LittleEndian>() {
         Err(err) => panic!("Error in reading {:?}", err),
-        Ok(v) => Ok(vm.ctx.new_float(v as f64)),
+        Ok(v) => Ok(vm.ctx.new_float(f64::from(v))),
     }
 }
 

vm/src/stdlib/time_module.rs

@@ -17,7 +17,7 @@ fn time_sleep(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
 }
 
 fn duration_to_f64(d: Duration) -> f64 {
-    (d.as_secs() as f64) + ((d.subsec_nanos() as f64) / 1e9)
+    (d.as_secs() as f64) + (f64::from(d.subsec_nanos()) / 1e9)
 }
 
 fn time_time(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {