util/cbfstool: Enable "ms-extensions" compiler flag on mingw only

The flag activates some Win32 compatibility quirks and on
clang/openbsd it enables so many of them that the code doesn't compile
anymore. Therefore move it into the "Win32 area" in that Makefile.

Change-Id: Ic77c04941e40a568f1d74cec09eb3d22a66e69b0
Signed-off-by: Patrick Georgi <patrick@coreboot.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/78724
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions