gralloc: add dump buffer(s)

Add functions to IMapper to dump a buffer and to dump all the
buffers in the current process. The dump includes
all gettable or settable metadata.

Bug: 141632317
Test: VtsHalGraphicsMapperV4_0TargetTest

Change-Id: Iaa54b899aef185867b3fd66025c0eb251a9a7bd1
2 files changed