Remove compiler versioncheck from gpAux

The gpAux Makefile was checking for GCC version to ensure that GPDB
is compiled with the minimum version required. This is a layering
violation since we should be doing these checks in autoconf. Should
the compiler be let through autoconf then we are good to go, further
checking should not (need to) be performed.

The version checked for is also quite ancient by now, the odds of
it being the compiler on a system which can compile the rest of the
codebase is slim to none.
Reviewed-by: NBradford D. Boyle <bboyle@pivotal.io>

gpAux/Makefile

@@ -30,7 +30,7 @@ all : devel
 # Internal functions which are invoked by other rules within this makefile
 .PHONY : mgmtcopy copylibs
 .PHONY : greenplum_path RECONFIG HOMEDEP GPROOTDEP GPROOTDEP GPROOTFAIL
-.PHONY : gccVersionCheck clients
+.PHONY : clients
 
 #---------------------------------------------------------------------
 # Make 3rd-party libraries and tools
@@ -340,9 +340,9 @@ devel : CONFIGFLAGS+= --enable-cassert --enable-debug --enable-depend
 ifdef ENABLE_VPATH_BUILD
 devel : BUILDDIR=Debug
 devel : ISCONFIG=$(BUILDDIR)/GNUmakefile
-devel : gccVersionCheck HOMEDEP Debug/GNUmakefile
+devel : HOMEDEP Debug/GNUmakefile
 else
-devel : gccVersionCheck HOMEDEP $(ISCONFIG)
+devel : HOMEDEP $(ISCONFIG)
 endif
 	$(BUILD_STEPS)
 
@@ -356,9 +356,9 @@ dist : CLIENTSINSTLOC=$(CLIENTSDISTPATH)
 ifdef ENABLE_VPATH_BUILD
 dist : BUILDDIR=Release
 dist : ISCONFIG=$(BUILDDIR)/GNUmakefile
-dist : gccVersionCheck GPROOTDEP RECONFIG Release/GNUmakefile
+dist : GPROOTDEP RECONFIG Release/GNUmakefile
 else
-dist : gccVersionCheck GPROOTDEP RECONFIG $(ISCONFIG)
+dist : GPROOTDEP RECONFIG $(ISCONFIG)
 endif
 	$(BUILD_STEPS)
 
@@ -368,10 +368,10 @@ dist_prof : CLIENTSINSTLOC=$(CLIENTSDISTPATH)
 ifdef ENABLE_VPATH_BUILD
 dist_prof : BUILDDIR=Release
 dist_prof : ISCONFIG=$(BUILDDIR)/GNUmakefile
-dist_prof : gccVersionCheck GPROOTDEP RECONFIG $(ISCONFIG)
+dist_prof : GPROOTDEP RECONFIG $(ISCONFIG)
 else
 dist_prof : ISCONFIG=../GNUmakefile
-dist_prof : gccVersionCheck GPROOTDEP RECONFIG $(ISCONFIG)
+dist_prof : GPROOTDEP RECONFIG $(ISCONFIG)
 endif
 	$(BUILD_STEPS)
 
@@ -379,10 +379,10 @@ dist_faultinj : CLIENTSINSTLOC=$(CLIENTSDISTPATH)
 ifdef ENABLE_VPATH_BUILD
 dist_faultinj : BUILDDIR=Release
 dist_faultinj : ISCONFIG=$(BUILDDIR)/GNUmakefile
-dist_faultinj : gccVersionCheck GPROOTDEP RECONFIG Release/GNUmakefile
+dist_faultinj : GPROOTDEP RECONFIG Release/GNUmakefile
 else
 dist_faultinj : ISCONFIG=../GNUmakefile
-dist_faultinj : gccVersionCheck GPROOTDEP RECONFIG $(ISCONFIG)
+dist_faultinj : GPROOTDEP RECONFIG $(ISCONFIG)
 endif
 	$(BUILD_STEPS)
 
@@ -551,7 +551,7 @@ PVK_FILESET = \
 
 pvk : INSTCFLAGS=$(OPTFLAGS)
 pvk : INSTLOC=$(DISTPATH)
-pvk : gccVersionCheck version GPROOTDEP
+pvk : version GPROOTDEP
 	cd $(GPMGMT)/bin && $(MAKE) stream
 	mkdir -p $(INSTLOC)/bin/lib
 	@for file in $(PVK_FILESET); do \
@@ -734,22 +734,3 @@ distclean :
 distprep : $(ISCONFIG)
 	@cd $(BUILDDIR) && $(MAKE) distprep
 
-#---------------------------------------------------------------------
-# More internal functions
-#---------------------------------------------------------------------
-
-gccVersionCheck :
-	@echo "Checking GCC version" ; \
-	$(BLD_CC) --version > /dev/null 2>&1 ; \
-	if [ $$? -ne 0 ] ; then \
-	    echo "Error running $(BLD_CC) --version" ; \
-	    $(BLD_CC) --version ; \
-	    exit 1 ; \
-	fi
-	@$(BLD_CC) --version | head -n 1 | cut -d' ' -f3 | egrep '[0-3]\.[0-4]\.[0-1]' > /dev/null 2>&1 ; \
-	if [ $$? -eq 0 ] ; then \
-	    echo "Error: GPDB must be compiled with GCC 3.4.2 or later." ; \
-	    echo "Current GCC version:" ; \
-	    $(BLD_CC) --version ; \
-	    exit 1 ; \
-	fi