drm/radeon: Remove unnecessary NULL test before kfree in 'radeon_connector_free_edid'

Fixes the below:

WARNING: kfree(NULL) is safe and this check is probably not required.

Cc: Christian König <[e-mail]>
Cc: Alex Deucher <[e-mail]>
Signed-off-by: Srinivasan Shanmugam <[e-mail]>
Reviewed-by: Alex Deucher <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/radeon/radeon_connectors.c

···
 {
 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
 
-	if (radeon_connector->edid) {
-		kfree(radeon_connector->edid);
-		radeon_connector->edid = NULL;
-	}
+	kfree(radeon_connector->edid);
+	radeon_connector->edid = NULL;
 }
 
 static int radeon_ddc_get_modes(struct drm_connector *connector)