All callers of locate_vbt just care about the file content and
immediately map the rdev for its content.
Instead of repeating this in all call sites, move that code to
locate_vbt.
Change-Id: I5b518e6c959437bd8f393269db7955358a786719
Signed-off-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-on: https://review.coreboot.org/21896
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
cba7316c26