fix building on 10.6.8
fix building on 10.6.8

added __APPLE_CC__ to IS_APPLE test

pranith/capstone,pranith/capstone,pranith/capstone,pranith/capstone,AmesianX/capstone,pranith/capstone,bigendiansmalls/capstone,AmesianX/capstone,pranith/capstone,bigendiansmalls/capstone,AmesianX/capstone,AmesianX/capstone,bigendiansmalls/capstone,bSr43/capstone,bigendiansmalls/capstone,bSr43/capstone,AmesianX/capstone,bigendiansmalls/capstone,AmesianX/capstone,bigendiansmalls/capstone,bSr43/capstone,bSr43/capstone,AmesianX/capstone,bSr43/capstone,pranith/capstone,bSr43/capstone,bSr43/capstone,bigendiansmalls/capstone