base-files: remove bbappend hacking on fstab

This approach breaks images which have Xen in DISTRO_FEATURES,
but are not booting under Xen (and mounting /proc/xen fails).

xencommons, xendriverdomain, or proc-xen.mount should take care of
mounting /proc/xen.

Signed-off-by: Chris Patterson <pattersonc@ainfosec.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>

recipes-core/base-files/base-files_3.%.bbappend

@@ -1,5 +0,0 @@
-do_install_append() {
-	if echo "${DISTRO_FEATURES}" | grep -q 'xen'; then
-		echo "xenfs                /proc/xen            xenfs      defaults              0  0" >> ${D}${sysconfdir}/fstab
-	fi
-}