Don't need a separate flags variable in armv7 pmap_clean_page() -

Don't need a separate flags variable in armv7 pmap_clean_page() -
just use the pv_flags.  ('Twas a copy-paste from arm's pmap_clean_page(),
which did need it.)

Also remove even less used flags variable from pmap_page_remove().

First part from a diff from aalm@ - thanks

ok kettenis@ "looks good" patrick@