[VXLAN] Option to customize local and remote ports

[spin-lock]

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Is your feature request related to a problem? Please describe.

Currently, when creating VXLAN interfaces through OPNsense GUI there's no option to customize local and remote ports. As a result, all VXLAN ifaces are created with default values (4789) for both local and remote ports.

Describe the solution you like

I would like to ask a feature to customize local and remote ports on VXLAN for various reasons - avoiding censorships, better entropy for ECMP balancing, etc. - so OPNsense can pass the vxlanlocalport and vxlanremoteport params to ifconfig when creating a VXLAN interface.

Describe alternatives you considered

Additional context

[Monviech]

@AdSchellevis I could do this if you want. Sounds pretty straight forward.

[AdSchellevis]

@Monviech sure, be my guest. Thanks in advance

[spin-lock]

Thank you guys. Much appreciated.

[Monviech]

#7048