Get rid of the last remnants of PROJECT_DIR

This disappeared when we stopped being "fptools" and became just "ghc"

compiler/Makefile

@@ -257,8 +257,6 @@ $(CONFIG_HS) : $(FPTOOLS_TOP)/mk/config.mk
 	@echo "cLdIsGNULd            = \"$(LdIsGNULd)\"" >> $(CONFIG_HS)
 	@echo "cLD_X		     :: String" >> $(CONFIG_HS)
 	@echo "cLD_X		     = \"$(LD_X)\"" >> $(CONFIG_HS)
-	@echo "cPROJECT_DIR          :: String" >> $(CONFIG_HS)
-	@echo "cPROJECT_DIR          = \"$(PROJECT_DIR)\"" >> $(CONFIG_HS)
 	@echo "cGHC_DRIVER_DIR_REL   :: String" >> $(CONFIG_HS)
 	@echo "cGHC_DRIVER_DIR_REL   = \"$(GHC_DRIVER_DIR_REL)\"" >> $(CONFIG_HS)
 	@echo "cGHC_TOUCHY_PGM       :: String" >> $(CONFIG_HS)

compiler/main/SysTools.lhs

@@ -167,13 +167,7 @@ initSysTools mbMinusB dflags
 	; let installed, installed_bin :: FilePath -> FilePath
               installed_bin pgm   =  top_dir </> pgm
 	      installed     file  =  top_dir </> file
-	      inplace dir   pgm   =  top_dir </> 
-#ifndef darwin_TARGET_OS
--- Not sure where cPROJECT_DIR makes sense, on Mac OS, building with
--- xcodebuild, it surely is a *bad* idea!  -=chak
-                                     cPROJECT_DIR </> 
-#endif
-                                     dir </> pgm
+	      inplace dir   pgm   =  top_dir </> dir </> pgm
 
 	; let pkgconfig_path
 		| am_installed = installed "package.conf"