libselinux: use -W and -Werror in utils

Add the flags and fix the one build break.

Signed-off-by: Eric Paris <eparis@redhat.com>
diff --git a/libselinux/utils/Makefile b/libselinux/utils/Makefile
index 9163967..6f5aa52 100644
--- a/libselinux/utils/Makefile
+++ b/libselinux/utils/Makefile
@@ -4,7 +4,7 @@
 BINDIR ?= $(PREFIX)/sbin
 _BINDIR ?= $(DESTDIR)/sbin
 
-CFLAGS ?= -Wall
+CFLAGS ?= -Werror -Wall -W
 override CFLAGS += -I../include -D_GNU_SOURCE $(EMFLAGS)
 LDLIBS += -L../src -lselinux -L$(LIBDIR)
 
diff --git a/libselinux/utils/getenforce.c b/libselinux/utils/getenforce.c
index 891c7b7..e5d19c5 100644
--- a/libselinux/utils/getenforce.c
+++ b/libselinux/utils/getenforce.c
@@ -3,7 +3,8 @@
 #include <stdlib.h>
 #include <selinux/selinux.h>
 
-int main(int argc __attribute__ ((unused)), char **argv)
+int main(int argc __attribute__ ((unused)),
+	 char **argv __attribute__ ((unused)))
 {
 	int rc;