Only honor LOCAL_SDK_VERSION when building apps.

When building for the system, we want openssl to have
FORTIFY_SOURCE protections. LOCAL_SDK_VERSION suppresses
these protections for compatibility reasons.

(cherry-picked from eb9b8f9ae5c9cdc9f1e68cf8a3c89f21978a90f7)

Change-Id: I8ad09b66623fc289d488c12c4268b796330c491c
2 files changed