Make gralloc enums unsigned

hardware/libhardware/include was being included with -isystem, which
hides warnings.  The gralloc enum values are used as bitmasks on
unsigned types, explicitly mark them values as unsigned in order to
force the type of the resulting enum to be unsigned.

Bug: 32018017
Test: m -j
Change-Id: Iea281480574e0a7a8413273983c76c2c0f9f7049
1 file changed