Fix 'saftey' and 'additional' typos noticed in the assumption series.
Reword the ASSUME_NO_ROLLBACK slightly to improve clarity.
Signed-off-by: Simon Glass <sjg@chromium.org>
Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20200302190255.51426-1-sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>