$NetBSD: patch-configure,v 1.1 2021/08/15 06:57:49 nia Exp $

Shell portability.

--- configure.orig	2020-07-25 18:24:07.000000000 +0000
+++ configure
@@ -3659,7 +3659,7 @@ else
   HAVE_WEBP="no"
 fi
 
-if test "$HAVE_WEBP" == "yes"; then
+if test "$HAVE_WEBP" = "yes"; then
 
 $as_echo "#define HAVE_WEBP 1" >>confdefs.h
 
