avcodec/cbs_av1: fix decoder/encoder_buffer_delay variable types

buffer_delay_length_minus_1 is five bits long, meaning decode_buffer_delay and
encoder_buffer_delay can have values up to 32 bits long.
Reviewed-by: Mark Thompson <sw@jkqxz.net>
Signed-off-by: James Almer <jamrial@gmail.com>

libavcodec/cbs_av1.h

@@ -87,8 +87,8 @@ typedef struct AV1RawSequenceHeader {
     uint8_t  seq_level_idx[AV1_MAX_OPERATING_POINTS];
     uint8_t  seq_tier[AV1_MAX_OPERATING_POINTS];
     uint8_t  decoder_model_present_for_this_op[AV1_MAX_OPERATING_POINTS];
-    uint8_t  decoder_buffer_delay[AV1_MAX_OPERATING_POINTS];
-    uint8_t  encoder_buffer_delay[AV1_MAX_OPERATING_POINTS];
+    uint32_t decoder_buffer_delay[AV1_MAX_OPERATING_POINTS];
+    uint32_t encoder_buffer_delay[AV1_MAX_OPERATING_POINTS];
     uint8_t  low_delay_mode_flag[AV1_MAX_OPERATING_POINTS];
     uint8_t  initial_display_delay_present_for_this_op[AV1_MAX_OPERATING_POINTS];
     uint8_t  initial_display_delay_minus_1[AV1_MAX_OPERATING_POINTS];