staging: lustre: llite: remove duplicate fiemap defines

 * replace struct ll_user_fiemap with struct fiemap
 * replace struct ll_fiemap_extent with struct fiemap_extent
 * remove kernel defined FIEMAP_EXTENT_* constants
 * remove kernel defined FIEMAP_FLAG_* flags
 * add member prefix for struct ll_fiemap_info_key

 * Add cl_object_operations::coo_fiemap().
 * Add cl_object_fiemap() to get FIEMAP mappings.

Signed-off-by: Bobi Jam <bobijam.xu@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5823
Reviewed-on: http://review.whamcloud.com/12535
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6201
Reviewed-on: http://review.whamcloud.com/13608


Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-by: Yang Sheng <yang.sheng@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>