Add simple test to check the functioning of retrieval of

pagesize()/pagesizes() after change to use aux vector. Note that
public function getosreldate() is different from libc-internal
__getosreldate() and does not use aux to fetch osreldate value.

MFC after:	1 month

tools/test/auxinfo/Makefile

@@ -0,0 +1,7 @@
+# $FreeBSD$
+
+PROG=	auxinfo
+NO_MAN=
+WARNS?=	6
+
+.include <bsd.prog.mk>

tools/test/auxinfo/auxinfo.c

@@ -0,0 +1,58 @@
+/*
+ * This file is in public domain.
+ * Written by Konstantin Belousov <kib@freebsd.org>
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/mman.h>
+#include <err.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <unistd.h>
+
+static void
+test_pagesizes(void)
+{
+	size_t *ps;
+	int i, nelem;
+
+	nelem = getpagesizes(NULL, 0);
+	if (nelem == -1)
+		err(1, "getpagesizes(NULL, 0)");
+	ps = malloc(nelem * sizeof(size_t));
+	if (ps == NULL)
+		err(1, "malloc");
+	nelem = getpagesizes(ps, nelem);
+	if (nelem == -1)
+		err(1, "getpagesizes");
+	printf("Supported page sizes:");
+	for (i = 0; i < nelem; i++)
+		printf(" %jd", (intmax_t)ps[i]);
+	printf("\n");
+}
+
+static void
+test_pagesize(void)
+{
+
+	printf("Pagesize: %d\n", getpagesize());
+}
+
+static void
+test_osreldate(void)
+{
+
+	printf("OSRELDATE: %d\n", getosreldate());
+}
+
+int
+main(int argc __unused, char *argv[] __unused)
+{
+
+	test_pagesizes();
+	test_pagesize();
+	test_osreldate();
+	return (0);
+}