mpg123 isn't used in 12.x

platform/xcode/liblove.xcodeproj/project.pbxproj

@@ -5395,11 +5395,9 @@
 					"$(PROJECT_DIR)/macosx/Frameworks/freetype.framework/Headers",
 					"$(PROJECT_DIR)/macosx/Frameworks/Lua.framework/Headers",
 					"$(PROJECT_DIR)/macosx/Frameworks/SDL2.framework/Headers",
-					"$(PROJECT_DIR)/macosx/Frameworks/mpg123.framework/Headers",
 					/Library/Frameworks/freetype.framework/Headers,
 					/Library/Frameworks/Lua.framework/Headers,
 					/Library/Frameworks/SDL2.framework/Headers,
-					/Library/Frameworks/mpg123.framework/Headers,
 				);
 				INFOPLIST_FILE = "macosx/liblove-macosx.plist";
 				LD_DYLIB_INSTALL_NAME = "@rpath/$(EXECUTABLE_PATH)";
@@ -5441,11 +5439,9 @@
 					"$(PROJECT_DIR)/macosx/Frameworks/freetype.framework/Headers",
 					"$(PROJECT_DIR)/macosx/Frameworks/Lua.framework/Headers",
 					"$(PROJECT_DIR)/macosx/Frameworks/SDL2.framework/Headers",
-					"$(PROJECT_DIR)/macosx/Frameworks/mpg123.framework/Headers",
 					/Library/Frameworks/freetype.framework/Headers,
 					/Library/Frameworks/Lua.framework/Headers,
 					/Library/Frameworks/SDL2.framework/Headers,
-					/Library/Frameworks/mpg123.framework/Headers,
 				);
 				INFOPLIST_FILE = "macosx/liblove-macosx.plist";
 				LD_DYLIB_INSTALL_NAME = "@rpath/$(EXECUTABLE_PATH)";
@@ -5488,11 +5484,9 @@
 					"$(PROJECT_DIR)/macosx/Frameworks/freetype.framework/Headers",
 					"$(PROJECT_DIR)/macosx/Frameworks/Lua.framework/Headers",
 					"$(PROJECT_DIR)/macosx/Frameworks/SDL2.framework/Headers",
-					"$(PROJECT_DIR)/macosx/Frameworks/mpg123.framework/Headers",
 					/Library/Frameworks/freetype.framework/Headers,
 					/Library/Frameworks/Lua.framework/Headers,
 					/Library/Frameworks/SDL2.framework/Headers,
-					/Library/Frameworks/mpg123.framework/Headers,
 				);
 				INFOPLIST_FILE = "macosx/liblove-macosx.plist";
 				LD_DYLIB_INSTALL_NAME = "@rpath/$(EXECUTABLE_PATH)";