patch 9.0.1964: xattr support fails to build on MacOS X

Problem:  xattr support fails to build on MacOS X
Solution: Disable xattr support for MacOS X

MacOS X uses the same headers and functions sys/xattr.h but the function
signatures for xattr support are much different, so building fails.

So let's for now disable xattr support there.

closes: #13230
closes: #13232

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/version.c b/src/version.c
index f918ad8..0c65d7b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1964,
+/**/
     1963,
 /**/
     1962,