bootstrap: Cleanup FLAGS definition

The reorganisation is partly to avoid long lines but also to provide a
clear machanism for adding further flags and an easy approach to
disabling flags if desired (by commenting out the line).

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: I5310d166086c5d7f028be4e8c59c8db6b079a488
diff --git a/bootstrap.sh b/bootstrap.sh
index ac02a30..cf2cd9b 100755
--- a/bootstrap.sh
+++ b/bootstrap.sh
@@ -4,7 +4,6 @@
 
 autoreconf -f -i
 
-
 BOOTSTRAP_MODE=""
 
 if [ $# -gt 0 ];
@@ -15,10 +14,12 @@
 
 case "${BOOTSTRAP_MODE}" in
     dev)
-        FLAGS="-fsanitize=address,leak,undefined -Wformat -Werror=format-security -Werror=array-bounds -ggdb"
+        FLAGS="-Wformat -Werror=format-security"
+        FLAGS="${FLAGS} -Werror=array-bounds"
+        FLAGS="${FLAGS} -fsanitize=address,leak,undefined"
+        FLAGS="${FLAGS} -ggdb"
         ./configure \
             CFLAGS="${FLAGS}" \
-            CXXFLAGS="${FLAGS}" \
             --enable-code-coverage \
             "$@"
         ;;