Profile build options

I went through all the individual compile options that differ between
-fprofile-generate/-fprofile-use  and  -fprofile-arcs/-fbranch-probabilities
and distilled the speed difference down to only turning off
-fno-peel-loops and -fno-tracer.  Using this we still get the full speedup
(maybe a bit more because other optimizations stay on) and it's also much cleaner
because we can get rid of the "@rm -f ucioption.gc*" hack for all versions of gcc.

No functional change.

Resolves #237

src/Makefile

@@ -447,16 +447,13 @@ gcc-profile-prepare:
 
 gcc-profile-make:
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) \
-	EXTRACXXFLAGS='-fprofile-arcs' \
+	EXTRACXXFLAGS='-fprofile-generate' \
 	EXTRALDFLAGS='-lgcov' \
 	all
 
 gcc-profile-use:
-# Deleting corrupt ucioption.gc* profile files is necessary to avoid an 
-# "internal compiler error" for gcc versions 4.7.x
-	@rm -f ucioption.gc*
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) \
-	EXTRACXXFLAGS='-fbranch-probabilities' \
+	EXTRACXXFLAGS='-fprofile-use -fno-peel-loops -fno-tracer' \
 	EXTRALDFLAGS='-lgcov' \
 	all