Forgot to init c->sao_edge_filter[idx] when idx=0/1/2/3.
After this patch, the speedup of decoding H265 4K 30FPS
30Mbps on 3A6000 is about 7% (42fps==>45fps).
Change-Id: I521999b397fa72b931a23c165cf45f276440cdfb
Reviewed-by: yinshiyou-hf@loongson.cn
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>