Make the gcc build system create multiple libgcc.a instances for
different ABIs.
Change-Id: I1c888bf751bf43566da8927ed0aedb53857363bf
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-on: https://review.coreboot.org/13625
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>