Get rid of -fno-omit-frame-pointer

It costs a bit of performance. And it's trivial to re-enable
for debug/profiling purposes.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/Makefile b/Makefile
index 3589770..8473238 100644
--- a/Makefile
+++ b/Makefile
@@ -4,7 +4,7 @@
 DEBUGFLAGS = -D_FORTIFY_SOURCE=2 -DFIO_INC_DEBUG
 CPPFLAGS= -D_GNU_SOURCE -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 \
 	$(DEBUGFLAGS)
-OPTFLAGS= -O3 -fno-omit-frame-pointer -g $(EXTFLAGS)
+OPTFLAGS= -O3 -g $(EXTFLAGS)
 CFLAGS	= -std=gnu99 -Wwrite-strings -Wall $(OPTFLAGS)
 LIBS	= -lm $(EXTLIBS)
 PROGS	= fio