Unable to repack vehicle magazines.

[Drofseh]

Mods (complete and add to the following information):

• Arma 3: 2.16
• CBA: 3.17.1
• ACE3: 3.17.1

Description:
When manually reloading vehicle magazines you end up with a bunch of partial magazines (mostly for MGs, but it's possible for other mags as well) and no way to merge those magazines to get full ones again.

Steps to reproduce:

1. Pick any armed vehicle with more than 1 of the same magazine class.
2. Shoot a few rounds, reload, shoot a few from the next mag, reload, continue until each mag is a partial.
3. Try to repack magazines find you are unable to do so.
4. Cry when you are stuck with a bunch of partials

Expected behavior:
Repacking magazines should be extended to vehicle magazines, but it must take into account that empty magazines need to be preserved for ACE Rearm in order to be able to rearm custom ammo loadouts.

[johnb432]

For future reference: #9398 (comment)