tests: Avoid test bug-884597.t to loop infinitely

If some unexpected error happens while this test is trying to
create a linkto file, an infinite loop is generated and the test
never ends.

This patch limits the number of retries it can do to find that
file.

Change-Id: Ie556c509116109ead99c78d671b2669b4428faac
Signed-off-by: Xavier Hernandez <xhernandez@datalab.es>
Reviewed-on: http://review.gluster.org/8318
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>