(request) Melon DS Mac address input

I noticed an important setting is missing in Bizhawk: the Mac address insertion.
But more important, even using a dumped fimware (ds or dsi) the stored mac address is just overridden, moreso even disabling the firmware override (and clear nand) the ds and dsi still have a pre configured wifi connection from melonds rather than the one from the dumped firmware, similarly to the overridden mac address.

Melon DS already supports manually inserting a mac address to replicate the one you use on the console , and by default it doesn't override your own firmware's wifi connection settings and Mac address.
Using a personal mac address is fundamental to RNG on pokemon games using the same profile you would use on a console, without being locked to an emulator-specific profile.

Start by locating BizHawk's Melon DS core settings and the UI entry point for emulator-specific configuration. Compare the requested manual MAC address input with how firmware Wi-Fi settings are currently selected. Done means users can enter a personal MAC address and use the corresponding firmware connection settings for DS and DSi games.