Turn-off implicit GNU Make RC/SCCS rules

This small patch prevents GNU Make from stating RCS and SCCS
specific files on the filesystem. This makes the output of
"make -d" slightly more readable, and also reduces the no-change
time on AOSP master by a bit less than a second on average.

Change-Id: Ifa50ace32e8689717956d7247b0d6f53ef72b7a1