update.sh: Adds code to update an existing ovpnconfig with pass or no-pass

update.sh: Adds code to update an existing ovpnconfig with pass or no-pass

- The code checks first if ovpnconfig exists and is not empty.
- Then it makes all net2net connections no-pass since they do not use encryption
- Then it cycles through all .p12 files and checks with openssl if a password exists or not.
   If a password is present then pass is added to index 41 and if not then no-pass is added
   to index 41
- This code should be left in update.sh for future Core Updates in case people don't update
   with Core Update 175 but leave it till later. This code works fine on code that already
   has pass or no-pass entered into index 41 in ovpnconfig

Fixes: Bug#11048
Suggested-by: Erik Kapfer <ummeegge@ipfire.org>
Suggested-by: Adolf Belka <adolf.belka@ipfire.org>
Tested-by: Erik Kapfer <ummeegge@ipfire.org>
Tested-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>