futility: updater: revise building RW-recovery sections

When checking the sections to update in the RW-recovery flow, we should
always check the availability before adding them to the list for
updating.

BUG=None
TEST=build and run test
BRANCH=None

Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Change-Id: Id714b1db736cbf4eef879566431e5a496f319cd4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/3494671
Reviewed-by: Yu-Ping Wu <yupingso@chromium.org>
1 file changed