8216354: Syntax error in toolchain_windows.m4

Reviewed-by: erikj, dholmes, clanger

common/autoconf/toolchain_windows.m4

@@ -652,7 +652,7 @@ AC_DEFUN([TOOLCHAIN_SETUP_VS_RUNTIME_DLLS],
   if test "x$USE_UCRT" = "xtrue"; then
     AC_MSG_CHECKING([for UCRT DLL dir])
     if test "x$with_ucrt_dll_dir" != x; then
-      if test -z "$(ls -d "$with_ucrt_dll_dir/*.dll" 2> /dev/null)"; then
+      if test -z "$(ls -d "$with_ucrt_dll_dir/"*.dll 2> /dev/null)"; then
         AC_MSG_RESULT([no])
         AC_MSG_ERROR([Could not find any dlls in $with_ucrt_dll_dir])
       else