compositor: Move device coordinate transform helper to compositor.c
This function transform input coordinates from output space to
compositor space and is useful for X input as well as touch screen input.
diff --git a/src/compositor.h b/src/compositor.h
index 84f39e2..acaecbb 100644
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -1075,6 +1075,10 @@
int x, int y, int width, int height, uint32_t transform, int32_t scale);
void
weston_output_destroy(struct weston_output *output);
+void
+weston_output_transform_coordinate(struct weston_output *x11_output,
+ int device_x, int device_y,
+ wl_fixed_t *x, wl_fixed_t *y);
void
weston_seat_init(struct weston_seat *seat, struct weston_compositor *ec,