Fix libelf path

Fixes kernel build

Change-Id: Ic6cdb1734d7b865491e8e61403d32db4acafe514
Signed-off-by: Alvin Francis <nivlafx@gmail.com>
ASAN: set MAXIMUM_OVERDRIVE := true to disable address sanitizer

with respect to BONE_STOCK taking priority.

Address sanitizer is a debugging tool that detects memory errors in the program through debugging tools
like gdb. It does so by using an extra instrumentation module llvm pass during compilation and a runtime
library that replaces the malloc function and by inserting frame pointers in the stack.

Output code performance can be effected if a "hot" function that is known to speed up the code gets
flagged during the extra compiler pass.  This also potentially can reduce build time.

Change-Id: I7cdd2c10e37255b5f5b31f5999b6a9d530eb9493
Ensure the use of $ANDROID_BUILD_TOP/ccache/ccache unless USE_CCACHE is not set

Change-Id: I249d1387b7c289fad437f8e0752311531d6b1bef
testing ccache

Change-Id: I6ebc420bff240ebef7bf060469539251f0d0d46c