drm/vc4: Fix comment in vc4_drv.h

Fixes a copy&paste error.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: NEric Anholt <eric@anholt.net>
Link: http://patchwork.freedesktop.org/patch/msgid/1495550187-525-1-git-send-email-boris.brezillon@free-electrons.com

drivers/gpu/drm/vc4/vc4_drv.h

@@ -532,7 +532,7 @@ int vc4_queue_seqno_cb(struct drm_device *dev,
 extern struct platform_driver vc4_hdmi_driver;
 int vc4_hdmi_debugfs_regs(struct seq_file *m, void *unused);
 
-/* vc4_hdmi.c */
+/* vc4_vec.c */
 extern struct platform_driver vc4_vec_driver;
 int vc4_vec_debugfs_regs(struct seq_file *m, void *unused);