Missed a comma for the default case of sdks

git-svn-id: svn+ssh://svn.code.sf.net/p/mingw-w64/code/trunk@5192 4407c894-4637-0410-b4f5-ada5f102cad1
diff --git a/mingw-w64-headers/configure b/mingw-w64-headers/configure
index cf08f5f..a5260ec 100755
--- a/mingw-w64-headers/configure
+++ b/mingw-w64-headers/configure
@@ -2578,7 +2578,7 @@
 if test "${enable_sdk+set}" = set; then :
   enableval=$enable_sdk;
 else
-  enable_sdkall=
+  enable_sdk=all
 fi
 
 
diff --git a/mingw-w64-headers/configure.ac b/mingw-w64-headers/configure.ac
index bf9133d..7b60fe7 100644
--- a/mingw-w64-headers/configure.ac
+++ b/mingw-w64-headers/configure.ac
@@ -74,7 +74,7 @@
   [AS_HELP_STRING([--enable-sdk=ARG],
     [Add the desired SDK, where ARG can be one of ddk, directx, no or all.  Default is all.])],
   [],
-  [AS_VAR_SET([enable_sdk][all])])
+  [AS_VAR_SET([enable_sdk],[all])])
 
 AS_CASE([$enable_sdk],
   [all|yes],[