Fix mma build: 'cd bionic && mma' case

Bug: 17887283
Change-Id: If2015f2361348eac8c53aed3f8715077b79ce2f5
Merge "Fix mma build: 'cd bionic && mma' case"
Replace uses of sprintf(3) with snprintf(3).

At -00, the compiler warns about sprintf(3), and it is promoted to an
error by -Werror.

Change-Id: Ibb380d27d7eb09dda8ac785be2478d656b379190
Build dlext_testzip as custom module.

Use $(BUILD_SYSTEM)/base_rules to build it as custom module, so that
it's exposed to utilities like mm/mmma etc.

Bug: 17887283
Change-Id: Idd7b62d08e4d56331a3ff15da6aa46eae8c41898
Merge "Build dlext_testzip as custom module."
Merge "Replace uses of sprintf(3) with snprintf(3)."