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_atomic_plane.c b/drivers/gpu/drm/i915/intel_atomic_plane.c
index 98288d8..b82de30 100644
--- a/drivers/gpu/drm/i915/intel_atomic_plane.c
+++ b/drivers/gpu/drm/i915/intel_atomic_plane.c
@@ -143,7 +143,7 @@
 		crtc_state->base.enable ? crtc_state->pipe_src_h : 0;
 
 	if (state->fb && intel_rotation_90_or_270(state->rotation)) {
-		const char *format_name;
+		char *format_name;
 		if (!(state->fb->modifier[0] == I915_FORMAT_MOD_Y_TILED ||
 			state->fb->modifier[0] == I915_FORMAT_MOD_Yf_TILED)) {
 			DRM_DEBUG_KMS("Y/Yf tiling required for 90/270!\n");