media: mtk-vcodec: vdec: remove redundant 'pfb' assignment

A clang-analyzer warning was reported.

>> drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_stateless.c:133:18:
   warning: Value stored to 'pfb' during its initialization is never
   read [clang-analyzer-deadcode.DeadStores]

            struct vdec_fb *pfb = &framebuf->frame_buffer;
                            ^~~   ~~~~~~~~~~~~~~~~~~~~~~~

Removes the redundant 'pfb' assignment to fix.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

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

@@ -133,7 +133,6 @@ static struct vdec_fb *vdec_get_cap_buffer(struct mtk_vcodec_ctx *ctx,
 	struct vdec_fb *pfb = &framebuf->frame_buffer;
 	struct vb2_buffer *dst_buf = &vb2_v4l2->vb2_buf;
 
-	pfb = &framebuf->frame_buffer;
 	pfb->base_y.va = NULL;
 	pfb->base_y.dma_addr = vb2_dma_contig_plane_dma_addr(dst_buf, 0);
 	pfb->base_y.size = ctx->q_data[MTK_Q_DATA_DST].sizeimage[0];