Remove python pyc file when uninstall rpm

Remove python pyc file when uninstall rpm.

Change-Id: I6520b51aac34060b5b90f94a016cec1827a4973f


[ROCm/rocm_smi_lib commit: 42f11bdd63]

projects/rocm-smi-lib/RPM/postun.in

@@ -4,3 +4,6 @@ if [ $1 -le 1 ] && [ "@ENABLE_LDCONFIG@" == "ON" ]; then
     rm -f /etc/ld.so.conf.d/x86_64-librocm_smi_lib.conf
     ldconfig
 fi
+
+# remove pyc file generated by python
+rm -rf @CPACK_PACKAGING_INSTALL_PREFIX@/libexec/rocm_smi/__pycache__