fix bug in rebuild rule of makefile
fix bug in rebuild rule of makefile

RJ/relx,umatomba/relx,syl20bnr/relx,zugolosian/relx,ethercrow/relx,tsloughter/relx,lrascao/relx,ingwinlu/relx,timclassic/relx,bitwalker/relx,erlware/relx,Licenser/relx,priestjim/relx,bsmr-erlang/relx