qcacmn: Add qdf_platform source file to qdf/Kbuild

Add qdf_platform source file to qdf/Kbuild and
clean-up WAR introduced in change
I8172f3dbe0716be24a4dda739afb49f94528a4f6

Change-Id: Icb76d53544590b8bcace275ef52870606fb5d826
diff --git a/qdf/Kbuild b/qdf/Kbuild
index ad992f7..403b383 100644
--- a/qdf/Kbuild
+++ b/qdf/Kbuild
@@ -53,6 +53,7 @@
 src/qdf_parse.o \
 src/qdf_str.o \
 src/qdf_types.o \
+src/qdf_platform.o \
 $(HOST_CMN_CONVG_NLINK)/src/wlan_nlink_srv.o \
 $(HOST_CMN_CONVG_SRC)/qal/linux/src/qal_devcfg.o \
 $(HOST_CMN_CONVG_SRC)/qal/linux/src/qal_vbus_dev.o \