media: mtk-vcodec: Remove duplicated include in mtk_vcodec_enc_drv.c

Fix following includecheck warning:
./drivers/media/platform/mtk-vcodec/mtk_vcodec_enc_drv.c:
linux/pm_runtime.h is included more than once.
Reported-by: NAbaci Robot <abaci@linux.alibaba.com>
Signed-off-by: NYang Li <yang.lee@linux.alibaba.com>
Signed-off-by: NHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/mtk-vcodec/mtk_vcodec_enc_drv.c

@@ -15,7 +15,6 @@
 #include <media/v4l2-event.h>
 #include <media/v4l2-mem2mem.h>
 #include <media/videobuf2-dma-contig.h>
-#include <linux/pm_runtime.h>
 
 #include "mtk_vcodec_drv.h"
 #include "mtk_vcodec_enc.h"