src/descriptors/dr_8a.c: implement b_duplicate flag
src/descriptors/dr_8a.c: implement b_duplicate flag

The function did not implement b_duplicate flag, while all other
descriptors do.

avble/libdvbpsi,mwgoldsmith/dvbpsi,Boxee/libdvbpsi,hiroshiyui/libdvbpsi,vlc-mirror/libdvbpsi,mkrufky/libdvbpsi,hiroshiyui/libdvbpsi,krieger-od/libdvbpsi,garbear/libdvbpsi,paraeco/libdvbpsi,paraeco/libdvbpsi,UIKit0/libdvbpsi,krieger-od/libdvbpsi,vlc-mirror/libdvbpsi,mkrufky/libdvbpsi,mkrufky/libdvbpsi,mwgoldsmith/dvbpsi,garbear/libdvbpsi,Boxee/libdvbpsi,hiroshiyui/libdvbpsi,UIKit0/libdvbpsi,paraeco/libdvbpsi,garbear/libdvbpsi,paraeco/libdvbpsi,krieger-od/libdvbpsi,mwgoldsmith/dvbpsi,avble/libdvbpsi,Boxee/libdvbpsi,vlc-mirror/libdvbpsi,mwgoldsmith/dvbpsi,UIKit0/libdvbpsi,avble/libdvbpsi