Build: Add DWARF version

Add BUILD_DWARF_VERSION to indicate which DWARF version to use. Set it
to a special value when building, such as: "-DBUILD_DWARF_VERSION=2".

Change-Id: I20370cac9588dba7636d2ec404f7c674ef6bdd16
Signed-off-by: Edison Ai <edison.ai@arm.com>
3 files changed