Enable address sanitizer, credits to @chipitsine

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

check.sh

@@ -3,5 +3,6 @@
 
 make distclean
 ./configure --prefix=/usr --exec-prefix= --sysconfdir=/etc --localstatedir=/var \
-	    --enable-x11-common-plugin --with-watchdog --with-keventd
+	    --enable-x11-common-plugin --with-watchdog --with-keventd \
+	    CFLAGS='-fsanitize=address -ggdb'
 make -j17 clean check