recipes: pre/post actions

A number of the recipes did not properly label their pre and post
actions, causing the actions to occur in all split packages.  This
was corrected by defaulting to _${PN} in most cases.

Signed-off-by: Mark Hatle <mark.hatle@windriver.com>

meta/recipes-core/base-passwd/base-passwd_3.5.22.bb

@@ -40,7 +40,7 @@ do_install_append_openmn() {
 }
 
 
-pkg_postinst () {
+pkg_postinst_${PN} () {
 	set -e
 
 	if [ ! -e $D${sysconfdir}/passwd ] ; then