build: Add Qualcomm's helper macros

 * This is used everywhere in Qualcomm's code. There's no reason we need
   to constantly replace it with uglier stuff in our Makefiles.

Change-Id: I0183a338470ec96a38f356a47bae65a0d3fb2c95
Merge "build: Add Qualcomm's helper macros" into android-4.4