Fix preprocessor directive for iOS build
Fix preprocessor directive for iOS build

rpowelll/ReactiveCocoa,tonyarnold/ReactiveCocoa,Juraldinio/ReactiveCocoa,natestedman/ReactiveCocoa,natestedman/ReactiveCocoa,tonyarnold/ReactiveCocoa,kevin-zqw/ReactiveCocoa,ohwutup/ReactiveCocoa,andersio/ReactiveCocoa,llb1119/test,walkingsmarts/ReactiveCocoa,ikesyo/ReactiveCocoa,ohwutup/ReactiveCocoa,calebd/ReactiveCocoa,victorlin/ReactiveCocoa,victorlin/ReactiveCocoa,beni55/ReactiveCocoa,tzongw/ReactiveCocoa,victorlin/ReactiveCocoa,Juraldinio/ReactiveCocoa,tzongw/ReactiveCocoa,esttorhe/ReactiveCocoa,calebd/ReactiveCocoa,llb1119/test,tonyarnold/ReactiveCocoa,esttorhe/ReactiveCocoa,ReactiveCocoa/ReactiveSwift,walkingsmarts/ReactiveCocoa,walkingsmarts/ReactiveCocoa,kevin-zqw/ReactiveCocoa,yonekawa/ReactiveCocoa,esttorhe/ReactiveCocoa,Farteen/ReactiveCocoa,ikesyo/ReactiveCocoa,Farteen/ReactiveCocoa,sandyway/ReactiveCocoa,paulyoung/ReactiveCocoa,yonekawa/ReactiveCocoa,sandyway/ReactiveCocoa,tzongw/ReactiveCocoa,ReactiveCocoa/ReactiveSwift,llb1119/test,smilypeda/ReactiveCocoa,ohwutup/ReactiveCocoa,ReactiveCocoa/ReactiveSwift,Juraldinio/ReactiveCocoa,esttorhe/ReactiveCocoa,sandyway/ReactiveCocoa,RuiAAPeres/ReactiveCocoa,RuiAAPeres/ReactiveCocoa,rpowelll/ReactiveCocoa,rpowelll/ReactiveCocoa,smilypeda/ReactiveCocoa,beni55/ReactiveCocoa,andersio/ReactiveCocoa,natestedman/ReactiveCocoa,Farteen/ReactiveCocoa,yonekawa/ReactiveCocoa,kevin-zqw/ReactiveCocoa,smilypeda/ReactiveCocoa,RuiAAPeres/ReactiveCocoa,beni55/ReactiveCocoa,paulyoung/ReactiveCocoa,calebd/ReactiveCocoa,paulyoung/ReactiveCocoa,andersio/ReactiveCocoa