dtoc: Allow overriding cc with $CC

Our build system isn't particularly happy about using cc
directly and fails the build when doing so.

BUG=b:181337770
TEST=zephyr's zmake, which uses binman, which uses dtoc,
successfully builds kohaku as part of emerge-hatch chromeos-zephyr

Signed-off-by: Patrick Georgi <pgeorgi@google.com>
Change-Id: I0c040ab195ac33d48fe03ebed67fbd8c424334c2
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/u-boot/+/2775734
Tested-by: Patrick Georgi <pgeorgi@chromium.org>
Auto-Submit: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Commit-Queue: Simon Glass <sjg@chromium.org>
1 file changed