LU-2123 tests: sanity 57 and 129 can't detect fstype

LU-2123 tests: sanity 57 and 129 can't detect fstype

In sanity test 57a,57b and 129 the function facet_type_fstype
is used to determine the file system backend. This function
does not actually exist so this test never run for the
ldiskfs case. The fix is to use the proper function which
is facet_fstype.

Signed-off-by: James Simmons <uja.ornl@gmail.com>
Change-Id: Ia9766a3a2200c6ce2d48ff0265eb73a4d71c06e7
Reviewed-on: http://review.whamcloud.com/4230
Tested-by: Hudson
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Li Wei <liwei@whamcloud.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Yu Jian <yujian@whamcloud.com>