sys-block/open-iscsi: fix mishandling of MY_PV

The code to set up MY_PV was based on MY_PV which mean successive env
loads would generate an incorrect value.  Drop the loading of it (as
the default PV is what we want) and rename the var to MY_P as that is
what it actually represents.

sys-block/open-iscsi/open-iscsi-2.0.873.ebuild

@@ -6,11 +6,11 @@ EAPI=5
 
 inherit versionator linux-info eutils flag-o-matic toolchain-funcs
 
-MY_PV="${PN}-$(replace_version_separator 2 "-" $MY_PV)"
+MY_P="${PN}-$(replace_version_separator 2 "-")"
 
 DESCRIPTION="Open-iSCSI is a high performance, transport independent, multi-platform implementation of RFC3720"
 HOMEPAGE="http://www.open-iscsi.org/"
-SRC_URI="http://www.open-iscsi.org/bits/${MY_PV}.tar.gz"
+SRC_URI="http://www.open-iscsi.org/bits/${MY_P}.tar.gz"
 
 LICENSE="GPL-2"
 SLOT="0"
@@ -22,7 +22,7 @@ RDEPEND="${DEPEND}
 	sys-fs/lsscsi
 	sys-apps/util-linux"
 
-S="${WORKDIR}/${MY_PV}"
+S="${WORKDIR}/${MY_P}"
 
 pkg_setup() {
 	linux-info_pkg_setup