multimedia/obs-studio: Update 21.0.3 -> 21.1.1

Port changes:

• Take maintainership
• Change to DISTVERSION
• Add swig30 to BUILD_DEPENDS
• Sort and add to LIB_DEPENDS
• Add lua and python to USES
• Change GH_ACCOUNT to developer's account
• Sort USE_QT5
• Add to and sort USE_XORG
• Remove unnecessary INSTALLS_ICONS
• Remove unnecessary patch of -ldl in Linux-only code
• Now works with any python version 3.4+
• Now scripting works via python and lua