When files in /boot fail hash verification, the list of files
can sometimes overflow the whiptail msgbox, preventing the
prompt and buttons to update checksums from showing. To mitigate
this, if # of files is > 10, use less to show the file list and
present a separate prompt to update the checksums once the file
list has been viewed.
Signed-off-by: Matt DeVillier <matt.devillier@puri.sm>