Add GameCube Controller Profile Hotkeys

[kierio04]

[Applies to upstream too]

For some reason, the following hotkeys only exist for Wii Remote profiles, rather than GameCube Controller profiles:

• Next Profile
• Previous Profile
• Next Game Profile
• Previous Game Profile

[malleoz]

It isn't immediately obvious to me how this portion of the codebase operates, and this would require a good deal of time to adjust. Not an immediate priority I believe.

[malleoz]

This is a prerequisite before this can be implemented: dolphin-emu#10489