fs: remove the access_ok() check in ioctl_fiemap

access_ok just checks we are fed a proper user pointer.  We also do that
in copy_to_user itself, so no need to do this early.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20200523073016.2944131-9-hch@lst.de


Signed-off-by: Theodore Ts'o <tytso@mit.edu>