consitify do_mount() arguments

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
(cherry picked from commit 808d4e3cfdcc52b19276175464f6dbca4df13b09)
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>

Change-Id: I70d4c162ea08089335c08d253c92bb4da3711c5e
10 files changed