[PATCH v2 2/3] configure: Require widl >= 3.21.

[Giovanni Mascellani]

From: Giovanni Mascellani

Commit b7402ddbbecdfaa81daa657fbb5d37661f401434 from wine is required,
which was first released with 3.21, not 3.20.
---
 configure.ac | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index b58c2f4d2..213ab22ee 100644
--- a/configure.ac
+++ b/configure.ac
@@ -27,7 +27,7 @@ AC_PROG_CC
 AM_PROG_CC_C_O
 AC_PROG_SED
 AC_PROG_MKDIR_P
-VKD3D_PROG_WIDL(3, 20)
+VKD3D_PROG_WIDL(3, 21)
 AS_IF([test "x$WIDL" = "xno"], [AC_MSG_WARN([widl is required to build header files.])])

AC_CHECK_PROGS([FLEX], [flex], [none])