gluster-setup.sh does not mknodes on failed mount

[gonoph]

After the update in commit 2e2e284, gluster-setup.sh no longer attempts to mount failed bricks.

According to the man page RETURN CODE 1 is incorrect permissions or invocation (bad parameters). The previous commit attempted to only test for that error, which if continuing in the script logic allows the glusterd pod to attempt to identify the failed bricks, and try various tricks to mount them.

I recommend testing the script for RETURN CODE 1, 2, and 4 - which should cover most fatal errors, and still allow the script to attempt to mount failed bricks using the logic below that test.