$NetBSD$

Fix shell compatibility warning.

--- libraries/ilmbase/configure.orig	2021-07-08 09:56:01.000000000 +0000
+++ libraries/ilmbase/configure
@@ -17208,7 +17208,7 @@ LIB_SUFFIX=""
 lib_suffix_valid="no"
 
 lib_namespace=""
-if test "x${library_namespace_versioning}" == xyes ; then
+if test "x${library_namespace_versioning}" = xyes ; then
     cat >>confdefs.h <<_ACEOF
 #define IMATH_INTERNAL_NAMESPACE Imath_${ILMBASE_VERSION_API}
 _ACEOF
@@ -17229,7 +17229,7 @@ _ACEOF
     lib_namespace="${ILMBASE_VERSION_API}"
     LIB_SUFFIX="${ILMBASE_VERSION_API}"
     lib_suffix_valid="yes"
-elif test "x${library_namespace_versioning}" == xno ; then
+elif test "x${library_namespace_versioning}" = xno ; then
     cat >>confdefs.h <<_ACEOF
 #define IMATH_INTERNAL_NAMESPACE Imath
 _ACEOF
@@ -17267,7 +17267,7 @@ _ACEOF
 fi
 
 
-if test "x${lib_suffix_valid}" == xyes ; then
+if test "x${lib_suffix_valid}" = xyes ; then
 LIB_SUFFIX_DASH="-${LIB_SUFFIX}"
 
  if true; then
@@ -17302,7 +17302,7 @@ else
 fi
 
 
-if test "x${custom_public_namespace}" == xyes ; then
+if test "x${custom_public_namespace}" = xyes ; then
     { $as_echo "$as_me:$LINENO: WARNING: Enabling 'custom user namespace' requires an additional argument, reverting to default" >&5
 $as_echo "$as_me: WARNING: Enabling 'custom user namespace' requires an additional argument, reverting to default" >&2;}
     cat >>confdefs.h <<\_ACEOF
@@ -17320,7 +17320,7 @@ _ACEOF
 
     public_namespace=""
     custom_public_namespace=no
-elif test "x${custom_public_namespace}" == xno ; then
+elif test "x${custom_public_namespace}" = xno ; then
     cat >>confdefs.h <<\_ACEOF
 #define IMATH_NAMESPACE Imath
 _ACEOF