selftests: mlxsw: Make the unsplit array global in port_scale test

Currently, the array of the ports that were split in the port_scale test
is local, so the port_cleanup() unsplits an empty array.

Make the array global so the cleanup will be preformed properly.
Suggested-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/drivers/net/mlxsw/port_scale.sh

@@ -7,6 +7,8 @@
 
 PORT_NUM_NETIFS=0
 
+declare -a unsplit
+
 port_setup_prepare()
 {
 	:
@@ -20,12 +22,12 @@ port_cleanup()
 		devlink port unsplit $port
 		check_err $? "Did not unsplit $netdev"
 	done
+	unsplit=()
 }
 
 split_all_ports()
 {
 	local should_fail=$1; shift
-	local -a unsplit
 
 	# Loop over the splittable netdevs and create tuples of netdev along
 	# with its width. For example: