Fix for -native-symlinks

diff -r 262952236ff5 configure.ac
--- a/configure.ac	Sun Oct 11 11:33:09 2020 +0000
+++ b/configure.ac	Sun Oct 11 11:33:37 2020 +0000
@@ -65,6 +65,7 @@
 AC_PROG_RANLIB
 AC_PROG_MKDIR_P
 AM_PROG_CC_C_O
+AM_PROG_AR
 PKG_PROG_PKG_CONFIG