Wait longer for root device to become available

On some systems, it can take longer than 10 seconds for the root
disk to be detected.  Because enterprise hardware.  Increase the
wait time to 60 seconds so we don't incorrectly fail due to a
missing root device.

Change-Id: I4f67ef0295af8f2ae783fe3aea347b41987c6a66

elements/deploy-ironic/init.d/80-deploy-ironic

@@ -113,7 +113,7 @@ if [[ $ROOT_DEVICE ]]; then
 else
     t=0
     while ! target_disk=$(find_disk "$DISK"); do
-      if [ $t -eq 10 ]; then
+      if [ $t -eq 60 ]; then
         break
       fi
       t=$(($t + 1))