NanoBSD slow conf_mount_ro gives gateway timeout

[phil.davis]

If I have my nanoBSD system mounted read-only, when I try to save there is about a 60-second delay and then:

504 Gateway Time-out

This might be new in nginx - I think lighttpd was happy to wait a long time if conf_mount_ro took a long time.

If I go to the webGUI again, it takes some time to display. The file system still shows it is RW. After waiting more… finally the file system goes back to RO, and the change is successfully applied. So the action is continuing in the background.

Maybe the nginx timeout can be increased so that users who are willing to have their nanoBSD system in RO and put up with waiting to save can at least avoid being shown the gateway time-out.

[rbgarga]

For slow drivers you should keep it always rw as noted in:
https://doc.pfsense.org/index.php?title=2.2.4_New_Features_and_Changes

It's because of forcesync patch removal