qa/fsx: use the master branch to build the xfstest-dev

The upstream linux has removed ALLOCSP/FREESP ioctls, and also
the same with xfsprogs-devel package. So for the old xfstest-dev
the huild will fail, because it stil will depend on them.

Fixes: https://tracker.ceph.com/issues/64572
Signed-off-by: Xiubo Li <[email protected]>

Author: lxbsz

qa/workunits/suites/fsx.sh

@@ -4,7 +4,6 @@ set -e
 
 git clone https://git.ceph.com/xfstests-dev.git
 cd xfstests-dev
-git checkout 12973fc04fd10d4af086901e10ffa8e48866b735
 make -j4
 cd ..
 cp xfstests-dev/ltp/fsx .