HLE/Applets: Implemented a dummy Mii Selector applet.

This prevents some games (like Super Mario 3D Land) from freezing when trying to launch it, however, it's not complete and won't let you go past Mii selection as the parameter structure hasn't been reverse engineered yet.

src/core/CMakeLists.txt

@@ -26,6 +26,7 @@ set(SRCS
             hle/config_mem.cpp
             hle/hle.cpp
             hle/applets/applet.cpp
+            hle/applets/mii_selector.cpp
             hle/applets/swkbd.cpp
             hle/kernel/address_arbiter.cpp
             hle/kernel/event.cpp
@@ -155,6 +156,7 @@ set(HEADERS
             hle/function_wrappers.h
             hle/hle.h
             hle/applets/applet.h
+            hle/applets/mii_selector.h
             hle/applets/swkbd.h
             hle/kernel/address_arbiter.h
             hle/kernel/event.h