keyboard: Handle touch up event

This fixes arrow keys which trigger on button up.

Closes: https://bugs.freedesktop.org/show_bug.cgi?id=73169
diff --git a/clients/window.h b/clients/window.h
index cf8fc6c..57ff87b 100644
--- a/clients/window.h
+++ b/clients/window.h
@@ -521,6 +521,9 @@
 void
 input_get_position(struct input *input, int32_t *x, int32_t *y);
 
+int
+input_get_touch(struct input *input, int32_t id, float *x, float *y);
+
 #define MOD_SHIFT_MASK		0x01
 #define MOD_ALT_MASK		0x02
 #define MOD_CONTROL_MASK	0x04