include: Fix c++ compiler error with msxml2.idl.

This moves ISAXXMLFilter declaration after its base class ISAXXMLReader.
Otherwise the following error is shown in C++ mode

$ wineg++ test-msxml2.cpp
In file included from test-msxml2.cpp:1:
/usr/include/wine/windows/msxml2.h:16199:24: error: invalid use of incomplete type ‘struct ISAXXMLReader’
16199 | ISAXXMLFilter : public ISAXXMLReader
|                        ^~~~~~~~~~~~~
/usr/include/wine/windows/msxml2.h:644:19: note: forward declaration of ‘struct ISAXXMLReader’
644 | typedef interface ISAXXMLReader ISAXXMLReader;
|                   ^~~~~~~~~~~~~
winegcc: /usr/bin/g++ failed

Signed-off-by: Biswapriyo Nath <nathbappai@gmail.com>

include/msxml2.idl

@@ -2125,20 +2125,7 @@ interface ISAXLocator : IUnknown
 [
     local,
     object,
-    uuid(70409222-ca09-4475-acb8-40312fe8d145)
+    uuid(a4f96ed0-f829-476e-81c0-cdc7bd2a0802)
-]
-interface ISAXXMLFilter : ISAXXMLReader
-{
-    HRESULT getParent(
-        [out, retval] ISAXXMLReader ** pReader);
-    HRESULT putParent(
-        [in] ISAXXMLReader * reader);
-}
-
-[
-local,
-object,
-uuid (a4f96ed0-f829-476e-81c0-cdc7bd2a0802)
 ]
 interface ISAXXMLReader : IUnknown
 {
@@ -2192,6 +2179,19 @@ interface ISAXXMLReader : IUnknown
         [in] const WCHAR * url);
 }
 
+[
+    local,
+    object,
+    uuid(70409222-ca09-4475-acb8-40312fe8d145)
+]
+interface ISAXXMLFilter : ISAXXMLReader
+{
+    HRESULT getParent(
+        [out, retval] ISAXXMLReader ** pReader);
+    HRESULT putParent(
+        [in] ISAXXMLReader * reader);
+}
+
 [
     object,
     dual,