Minor drive-by simplification in RPC Makefile
Minor drive-by simplification in RPC Makefile

hoheinzollern/FStar,FStarLang/FStar,A-Manning/FStar,MallabaevAzamat/FStar,hoheinzollern/FStar,YaccConstructor/FStar,YaccConstructor/FStar,hoheinzollern/FStar,YaccConstructor/FStar,FStarLang/FStar,A-Manning/FStar,MallabaevAzamat/FStar,hoheinzollern/FStar,FStarLang/FStar,A-Manning/FStar,MallabaevAzamat/FStar,MallabaevAzamat/FStar,YaccConstructor/FStar