ui: introduce egl_init()

Future patches will introduce EGL support on win32 (too late for 8.0
though). Having a common place for EGL initialization and error handling
will make it simpler.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

ui/spice-core.c

@@ -820,12 +820,7 @@ static void qemu_spice_init(void)
                          "incompatible with -spice port/tls-port");
             exit(1);
         }
-        if (egl_rendernode_init(qemu_opt_get(opts, "rendernode"),
-                                DISPLAYGL_MODE_ON) != 0) {
-            error_report("Failed to initialize EGL render node for SPICE GL");
-            exit(1);
-        }
-        display_opengl = 1;
+        egl_init(qemu_opt_get(opts, "rendernode"), DISPLAYGL_MODE_ON, &error_fatal);
         spice_opengl = 1;
     }
 #endif