avcodec/options_table: make AVCodecContext->level search for child constants

This change makes it possible for child encoders to define custom level
option names which can be used for setting the AVCodecContext->level.

Based on 337fe4bc

Reviewed-by: jkqxz
Signed-off-by: NJames Almer <jamrial@gmail.com>

libavcodec/options_table.h

@@ -264,8 +264,8 @@ static const AVOption avcodec_options[] = {
 {"profile", NULL, OFFSET(profile), AV_OPT_TYPE_INT, {.i64 = FF_PROFILE_UNKNOWN }, INT_MIN, INT_MAX, V|A|E|CC, "avctx.profile"},
 {"unknown", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = FF_PROFILE_UNKNOWN }, INT_MIN, INT_MAX, V|A|E, "avctx.profile"},
 {"main10",  NULL, 0, AV_OPT_TYPE_CONST, {.i64 = FF_PROFILE_HEVC_MAIN_10 }, INT_MIN, INT_MAX, V|E, "avctx.profile"},
-{"level", NULL, OFFSET(level), AV_OPT_TYPE_INT, {.i64 = FF_LEVEL_UNKNOWN }, INT_MIN, INT_MAX, V|A|E, "level"},
-{"unknown", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = FF_LEVEL_UNKNOWN }, INT_MIN, INT_MAX, V|A|E, "level"},
+{"level", NULL, OFFSET(level), AV_OPT_TYPE_INT, {.i64 = FF_LEVEL_UNKNOWN }, INT_MIN, INT_MAX, V|A|E|CC, "avctx.level"},
+{"unknown", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = FF_LEVEL_UNKNOWN }, INT_MIN, INT_MAX, V|A|E, "avctx.level"},
 {"lowres", "decode at 1= 1/2, 2=1/4, 3=1/8 resolutions", OFFSET(lowres), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, V|A|D},
 #if FF_API_PRIVATE_OPT
 {"skip_threshold", "frame skip threshold", OFFSET(frame_skip_threshold), AV_OPT_TYPE_INT, {.i64 = DEFAULT }, INT_MIN, INT_MAX, V|E},