fate: add SCC test

Signed-off-by: Paul B Mahol <onemda@gmail.com>

.gitattributes

 *.pnm -diff -text
+tests/ref/fate/sub-scc eol=crlf

tests/fate/subtitles.mak

@@ -94,6 +94,9 @@ fate-sub-textenc: CMD = fmtstdout srt -i $(TARGET_SAMPLES)/sub/SubRip_capability
 FATE_SUBTITLES_ASS-$(call ALLYES, MICRODVD_DEMUXER MICRODVD_DECODER ICONV) += fate-sub-charenc
 fate-sub-charenc: CMD = fmtstdout ass -sub_charenc cp1251 -i $(TARGET_SAMPLES)/sub/cp1251-subtitles.sub
 
+FATE_SUBTITLES-$(call DEMDEC, SCC, CCAPTION) += fate-sub-scc
+fate-sub-scc: CMD = fmtstdout ass -ss 57 -i $(TARGET_SAMPLES)/sub/witch.scc
+
 FATE_SUBTITLES-$(call ENCMUX, ASS, ASS) += $(FATE_SUBTITLES_ASS-yes)
 FATE_SUBTITLES += $(FATE_SUBTITLES-yes)