fix build tracking.c should be tracking.o
fix build tracking.c should be tracking.o

thanks to @rafie
soveran/redis,charsyam/redis,soloestoy/redis,neomantra/redis,ctripcorp/redis,yossigo/redis,charsyam/redis,pmem/redis,ofirluzon/redis,ofirluzon/redis,neomantra/redis,pmem/redis,yossigo/redis,PKRoma/redis,antirez/redis,PKRoma/redis,neomantra/redis,oranagra/redis,charsyam/redis,ofirluzon/redis,yossigo/redis,PKRoma/redis,yossigo/redis,antirez/redis,charsyam/redis,oranagra/redis,soveran/redis,soloestoy/redis,pmem/redis,ctripcorp/redis,neomantra/redis,charsyam/redis,soveran/redis,PKRoma/redis,oranagra/redis,yossigo/redis,antirez/redis,ctripcorp/redis,antirez/redis,ctripcorp/redis,ofirluzon/redis,oranagra/redis,soloestoy/redis,soloestoy/redis,soloestoy/redis,oranagra/redis,pmem/redis,neomantra/redis,ofirluzon/redis,soveran/redis,PKRoma/redis