sds.c: Fix potential overflow in sdsll2str. (#8910)
sds.c: Fix potential overflow in sdsll2str. (#8910)

Fixes an undefined behavior, same way as our `ll2string` does.
PKRoma/redis,antirez/redis,PKRoma/redis,soloestoy/redis,neomantra/redis,charsyam/redis,ofirluzon/redis,antirez/redis,yossigo/redis,soloestoy/redis,ofirluzon/redis,PKRoma/redis,charsyam/redis,oranagra/redis,ofirluzon/redis,ofirluzon/redis,PKRoma/redis,oranagra/redis,PKRoma/redis,charsyam/redis,antirez/redis,charsyam/redis,soloestoy/redis,yossigo/redis,yossigo/redis,oranagra/redis,neomantra/redis,yossigo/redis,soloestoy/redis,soloestoy/redis,antirez/redis,yossigo/redis,neomantra/redis,ofirluzon/redis,oranagra/redis,neomantra/redis,charsyam/redis,neomantra/redis,oranagra/redis