build: Add SKIP_SET_METADATA flag

Reapplied the patch as it got lost in the 4.4.3 merge

On some of the older devices the recovery doesn't support
metadata when setting permissions. This allows to use
set_perm vs set_metadata.
Enable this behavior by setting SKIP_SET_METADATA := true

Conflicts:
	core/Makefile

Change-Id: Ib6cf97b5ca28cee8a87975231f3a61b156e77d29
Merge "build: Add SKIP_SET_METADATA flag" into android-4.4