media: hantro: Prevent encoders from using post-processing

The post-processing feature is meant to be used by decoding
only. Prevent encoding jobs from enabling it.

Fixes: 8c2d66b036c77 ("media: hantro: Support color conversion via post-processing")
Signed-off-by: Ezequiel Garcia <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/staging/media/hantro/hantro.h

···
 static inline bool
 hantro_needs_postproc(struct hantro_ctx *ctx, const struct hantro_fmt *fmt)
 {
-	return fmt->fourcc != V4L2_PIX_FMT_NV12;
+	return !hantro_is_encoder_ctx(ctx) && fmt->fourcc != V4L2_PIX_FMT_NV12;
 }
 
 static inline dma_addr_t