client: lseek shouldn't do permission checking

client: lseek shouldn't do permission checking

With the addition of the UserPerm changes, ceph_lseek started
checking for open permissions using the default mount perms. lseek
should not require those permissions though, as it operates on an
already-opened file descriptor. Remove the perms argument from most
of these functions.

Fixes: be9e43e2da41e91ffd8577dfd0b890cdb361a08e
Signed-off-by: Jeff Layton <jlayton@redhat.com>