bootloader: add DEBUG make flag

make DEBUG=1 tells uefi-build.sh to build the DEBUG target, which adds
lots of diagnostic messages that can be useful for people debugging
firmware or early-boot issues (e.g. register dumps in the default
exception handler).

Test: build and flash bootloader images built with and without DEBUG=1
Change-Id: Ic34f5dcc24336a166f15e260ebc88796f8701291
Signed-off-by: Greg Hackmann <ghackmann@google.com>
1 file changed