loader: add loader_open_render_node(..)

This helper is almost a 1:1 copy of tegra_open_render_node().

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>

src/loader/loader.h

@@ -38,6 +38,9 @@ extern "C" {
 int
 loader_open_device(const char *);
 
+int
+loader_open_render_node(const char *name);
+
 int
 loader_get_pci_id_for_fd(int fd, int *vendor_id, int *chip_id);