sh: check for existing mappings for bolted PMB entries.

When entries are being bolted unconditionally it's possible that the boot
loader has established mappings that are within range that we don't want
to clobber. Perform some basic validation to ensure that the new mapping
is out of range before allowing the entry setup to take place.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
1 file changed