Minor mountd.c cleanup

I find it more readable to have the normal (non-error) case unindented,
and to keep conditionals relatively simple, as is the usual kernel
style.  Fix some inconsistent indentation while we're there.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Steve Dickson <steved@redhat.com>