ext4: remove the call to fiemap_check_flags in ext4_fiemap

iomap_fiemap already calls fiemap_check_flags first thing, so this
additional check is redundant.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20200523073016.2944131-3-hch@lst.de


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