Fix numlock state

Apparantly, after activating numlock once, the numlock modifier
stays turned on (use xev(1) to verify). So, to resolve useful
keysyms, we remove the numlock flag from the event state. What
currently does not work is actually using your keypad.

i3-input/i3-input.h

@@ -8,7 +8,7 @@
 char *convert_ucs_to_utf8(char *input);
 char *convert_utf8_to_ucs2(char *input, int *real_strlen);
 uint32_t get_colorpixel(xcb_connection_t *conn, char *hex);
-uint32_t get_mode_switch_mask(xcb_connection_t *conn);
+uint32_t get_mod_mask(xcb_connection_t *conn, uint32_t keycode);
 int connect_ipc(char *socket_path);
 void ipc_send_message(int sockfd, uint32_t message_size,
                       uint32_t message_type, uint8_t *payload);