Add support for Slot 2 flashcarts using Compact Flash (#84)

- Supercard CF (SUPERCARDCF)
- GBA Media Player CF (MPCF)
- M3 Adapter CF (M3CF)
- Max Media Dock CF (MMCF)

arm9/source/patches/platform/compactflash-common/CompactFlashStatusFunctionsPatchCode.h

@@ -0,0 +1,32 @@
+#pragma once
+#include "common.h"
+#include "sections.h"
+#include "../LoaderPlatform.h"
+#include "CompactFlashRegisters.h"
+
+DEFINE_SECTION_SYMBOLS(cf_wait_functions);
+
+extern "C" bool cf_waitCardAvailableForCommands();
+extern "C" bool cf_waitNextBlockReady();
+
+extern vu16* cf_waitFunctions_reg_cmd;
+
+class CompactFlashStatusFunctionsPatchCode : public PatchCode
+{
+public:
+    CompactFlashStatusFunctionsPatchCode(PatchHeap& patchHeap, const cf_registers_t& registers)
+        : PatchCode(SECTION_START(cf_wait_functions), SECTION_SIZE(cf_wait_functions), patchHeap)
+    {
+        cf_waitFunctions_reg_cmd = registers.command;
+    }
+
+    const void* GetWaitCardAvailableForCommandsFunction() const
+    {
+        return GetAddressAtTarget((void*)cf_waitCardAvailableForCommands);
+    }
+
+    const void* GetWaitNextBlockReadyFunction() const
+    {
+        return GetAddressAtTarget((void*)cf_waitNextBlockReady);
+    }
+};