xpadneo: Map Share button to F12 by default

While desktop environments usually support mapping `KEY_RECORD`, most
importantly Steam does not recognize that key. So let's change the
driver to emit F12 instead which is the default screenshot key in the
Steam client.

This also seems to fix an issue with yet unknown cause: `KEY_RECORD`
would emit pressing the key and then immediately emit a release event.
With `KEY_F12` this properly emits one event on press, and emits a
second event on release.

Fixes: atar-axis#356
Signed-off-by: Kai Krakow <[email protected]>

hid-xpadneo/src/xpadneo.h

@@ -49,7 +49,7 @@ do { \
 
 /* button aliases */
 #define BTN_PADDLES(b) (BTN_TRIGGER_HAPPY37+(b))
-#define BTN_SHARE      KEY_RECORD
+#define BTN_SHARE      KEY_F12
 #define BTN_XBOX       BTN_MODE
 
 /* module parameter "trigger_rumble_mode" */