test/cuse: use waitforfile in revert function

lsblk used in waitforblk() works on blk device names
withouth full path (e.g. "nvme0n1"). This results in
a timeout because we pass "/dev/X" as an argument.
waitforfile() is the way to go in this case.

Signed-off-by: Karol Latecki <karol.latecki@intel.com>
Change-Id: I47a2b76bce6f15e0ffa2070e581bbf16f9647bdd
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/3694
Community-CI: Mellanox Build Bot
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: Maciej Wawryk <maciejx.wawryk@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

test/common/autotest_common.sh

@@ -1318,7 +1318,7 @@ function nvme_namespace_revert() {
 			nvme create-ns ${nvme_ctrlr} -s ${size} -c ${size} -b ${blksize}
 			nvme attach-ns ${nvme_ctrlr} -n 1 -c 0
 			nvme reset ${nvme_ctrlr}
-			waitforblk "${nvme_ctrlr}n1"
+			waitforfile "${nvme_ctrlr}n1"
 		fi
 	done
 }