Add rightx and righty for DreamPicoPort (for maraca support)
Add secondary d-pad to dreampicoport mapping
Allow DreamLink device to dictate button/axis name; set custom button names in DreamPicoPort to known codes
* added getFunctionDefinitions
* Set DreamPort device default deadzone to 0% while preserving user customization
* Fixed default dead zone 0% for DreamPicoPort; set UsePhysicalVmuMemory default to true
* Use DisabledScope for UsePhysicalVmuMemory; moved DreamLinkGamepad::getDefaultMapping() to protected scope to match parent
* Set unique ID for DreamPicoPort devices so they enumerate the same way by flycast on every load
* Implement DreamLinkGamepad::resetMappingToDefault() and set C, D, and Z buttons for DreamPicoPort
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Co-authored-by: Nexus382 <anthonyscordino@gmail.com>
James