Android: Add Slot A and B device settings to UI

Source/Android/app/src/main/res/values/strings.xml

@@ -117,6 +117,8 @@
     <string name="overclock_enable_description">Higher values can make variable-framerate games run at a higher framerate, requiring a powerful device. Lower values make games run at a lower framerate, increasing emulation speed, but reducing the emulated console\'s performance.</string>
     <string name="overclock_title">Emulated CPU Clock Speed</string>
     <string name="overclock_warning">WARNING: Changing this from the default (100%) WILL break games and cause glitches. Please do not report bugs that occur with a non-default clock.</string>
+    <string name="slot_a_device">GameCube Slot A Device</string>
+    <string name="slot_b_device">GameCube Slot B Device</string>
     <string name="wiimote_scanning">Wii Remote Continuous Scanning</string>
     <string name="wiimote_scanning_description">Leave this on if you are using a DolphinBar for real Wiimote support.</string>
     <string name="wiimote_speaker">Wii Remote Speaker</string>