Add Mahjong Fight Girl Support (#275)

## Link to GitHub Issue, if one exists
n/a

## Description of change
Adds Mahjong Fight Girl Support

## Compiling
+

## Testing
Tested with VFG:J:E:A:2024100800 in HG mode with VFG IO. No
modifications made to data, other than avs-config.xml and
ea3-config.xml. B and C modes don't work because of serial touchscreen.
UKS mode doesn't work because of IO.

src/spice2x/games/mfg/io.cpp

@@ -0,0 +1,23 @@
+#include "io.h"
+
+std::vector<Button> &games::mfg::get_buttons() {
+    static std::vector<Button> buttons;
+
+    if (buttons.empty()) {
+        buttons = GameAPI::Buttons::getButtons("Mahjong Fight Girl");
+
+        GameAPI::Buttons::sortButtons(
+                &buttons,
+                "Service",
+                "Test",
+                "Coin Mech"
+                //"Action Button"
+        );
+    }
+
+    return buttons;
+}
+
+std::string games::mfg::get_buttons_help() {
+    return "";
+}