drm: remove `const` attribute to hint at caller that they now own the memory

Signed-off-by: Eric Engestrom <eric.engestrom@imgtec.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index acc1ba3..3902e57 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -12258,7 +12258,7 @@
 
 	DRM_DEBUG_KMS("planes on this crtc\n");
 	list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
-		const char *format_name;
+		char *format_name;
 		intel_plane = to_intel_plane(plane);
 		if (intel_plane->pipe != crtc->pipe)
 			continue;
@@ -14915,7 +14915,7 @@
 	unsigned int aligned_height;
 	int ret;
 	u32 pitch_limit, stride_alignment;
-	const char *format_name;
+	char *format_name;
 
 	WARN_ON(!mutex_is_locked(&dev->struct_mutex));