input_common: Add support for GameCube Adapter

This is a port of the initial GameCube adapter input support i added into yuzu emulator.
It requires the same setup as when it was first introduced in yuzu, requiring the Zadig driver be installed for the adapter to allow it to interface with libusb.

src/input_common/CMakeLists.txt

@@ -1,6 +1,10 @@
 add_library(input_common STATIC
     analog_from_button.cpp
     analog_from_button.h
+    gcadapter/gc_adapter.cpp
+    gcadapter/gc_adapter.h
+    gcadapter/gc_poller.cpp
+    gcadapter/gc_poller.h
     keyboard.cpp
     keyboard.h
     main.cpp
@@ -30,3 +34,4 @@ endif()
 
 create_target_directory_groups(input_common)
 target_link_libraries(input_common PUBLIC core PRIVATE common ${Boost_LIBRARIES})
+target_link_libraries(input_common PUBLIC ${LIBUSB_LIBRARIES})