vfs: Enable FS_IOC_FIEMAP and FIGETBSZ for all filetypes

The fiemap and get_blk_size ioctls should be enabled even for
directories.  So move it outisde file_ioctl.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>