vboot: move VbExGetLocalizationCount to vboot2

Rename VbExGetLocalizationCount to vb2ex_get_locale_count.
Change signature to return by value instead of by parameter.

BUG=b:146399181, b:156070974
TEST=make clean && make runtests
BRANCH=none

Change-Id: I4e3986007034724f01c9d42a382398ddacd59f33
Signed-off-by: Joel Kitching <kitching@google.com>
Cq-Depend: chromium:2190612
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2193151
Tested-by: Joel Kitching <kitching@chromium.org>
Commit-Queue: Joel Kitching <kitching@chromium.org>
Reviewed-by: Yu-Ping Wu <yupingso@chromium.org>
6 files changed