wlr_texture: remove wlr_texture_from_wl_drm() from header

This function was already removed in e5b5592a but it was forgotten to
remove it from the header.

include/wlr/render/wlr_texture.h

@@ -33,16 +33,6 @@ struct wlr_texture *wlr_texture_from_pixels(struct wlr_renderer *renderer,
 	uint32_t fmt, uint32_t stride, uint32_t width, uint32_t height,
 	const void *data);
 
-/**
- * Create a new texture from a wl_drm resource. The returned texture is
- * immutable.
- *
- * Should not be called in a rendering block like renderer_begin()/end() or
- * between attaching a renderer to an output and committing it.
- */
-struct wlr_texture *wlr_texture_from_wl_drm(struct wlr_renderer *renderer,
-	struct wl_resource *data);
-
 /**
  * Create a new texture from a DMA-BUF. The returned texture is immutable.
  *