Add support for V2 Core Options and add option to set default controller.

[msheehan79]

This PR adds support for V2 Core Options and adds one core option to set the default controller as either Left or Right.

The V2 options required an update to the libretro.h file so I updated the libretro-common dependencies as part of this.

Tagging as draft here as the prior attempt at this broke MSVC builds. I use MinGW here and it compiled fine for me, but I don't have an MSVC setup to verify this won't impact those builds again, so would appreciate any input or confirmation that it compiles OK for those setups.

[inactive123]

Hi @m4xw , I'd like to merge this unless you have any objections.

[msheehan79]

@LibretroAdmin @m4xw any concerns with merging this PR?

I have a few other changes in my dev branch I would like to submit if this can be merged (input bitmasks, and full keypad mapping instead of the On Screen Keypad, similar to the changes I submitted for the a5200 core) which should address #81

[Jazzzed]

Yes please.