Removing the unneeded ExtraSymbols.symvers and cleaning up the FE makefile so...

Removing the unneeded ExtraSymbols.symvers and cleaning up the FE makefile so it builds on debian 11

Makefile.in

@@ -52,13 +52,10 @@ ifndef RCG_BUILD_NO_KOBJ
 # copy IOP symbol file to build area if found
 	@cp src/fe/ModuleIOP.symvers src/fe/$@ > /dev/null 2>&1 || /bin/true
 	@cat /opt/DIS/lib/modules/$(linux_version)/*.symvers > src/fe/$@/Module.symvers || /bin/true
-# build it
-	@make -C src/fe/$@ >> $@.log 2>>$@_error.log || (tail $@.log; cat $@_error.log && /bin/false)
-# save IOP symbol to file
-	@grep IOP src/fe/$@/Module.symvers > /tmp/tmp.symvers
-	@awk -vOFS='\t' '{$$3 = "/"; print}' /tmp/tmp.symvers > src/fe/ModuleIOP.symvers
-	@rm /tmp/tmp.symvers
+# build the FE model
 	@make -C src/fe/$@ >> $@.log 2>>$@_error.log || (tail $@.log; cat $@_error.log && /bin/false)
+	# save IOP symbol for other models, if we don't already have it 
+	@if [ ! -f src/fe/ModuleIOP.symvers ] ; then if grep IOP src/fe/$@/Module.symvers > /dev/null ; then grep IOP src/fe/$@/Module.symvers > src/fe/ModuleIOP.symvers; fi; fi
 	@$(srcdir)/src/epics/util/checkUndefined.pl $@_error.log >> $@.log 2>>$@_error.log || (tail $@.log; cat $@_error.log && /bin/false)
 	@echo Done
 endif

src/drv/ExtraSymbols.symvers

-0x00000000	vprintkl	/	EXPORT_SYMBOL

src/epics/util/lib/createKernelMakefile.pm

@@ -12,8 +12,7 @@ system ("/bin/cp GNUmakefile  ../../fe/$::skeleton");
 open(OUTM,">./".$fileName) || die "cannot open Makefile file for writing";
 
 print OUTM "# CPU-Shutdown Real Time Linux\n";
-print OUTM "KBUILD_EXTRA_SYMBOLS=$::rcg_src_dir/src/drv/ExtraSymbols.symvers\n";
-print OUTM "KBUILD_EXTRA_SYMBOLS += $::mbufsymfile\n";
+print OUTM "KBUILD_EXTRA_SYMBOLS = $::mbufsymfile\n";
 print OUTM "KBUILD_EXTRA_SYMBOLS += $::gpssymfile\n";
 print OUTM "KBUILD_EXTRA_SYMBOLS += $::cpuisolatorfile\n";
 print OUTM "KBUILD_EXTRA_SYMBOLS += \$(PWD)/ModuleIOP.symvers\n";