Removed duplicated call to AC_PROG_LIBTOOL

configure.ac

@@ -60,11 +60,10 @@ AM_CONDITIONAL(OS_WIN32, test "$os_win32" = "true")
 # Checks for programs.
 AC_PROG_CC
 AC_PROG_CXX
+AC_PROG_MAKE_SET
 AC_DISABLE_STATIC
 AC_LIBTOOL_WIN32_DLL
 AC_PROG_LIBTOOL
-AC_PROG_MAKE_SET
-AC_PROG_LIBTOOL
 AC_CHECK_HEADERS([ \
     termios.h \
     sys/time.h \