Preliminary support for OS X 10.11 (El Capitan) documentation. bz#348909.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15584 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/NEWS b/NEWS
index 203ef00..5f49719 100644
--- a/NEWS
+++ b/NEWS
@@ -10,6 +10,8 @@
 * x86: on an SSE2 only host, Valgrind in 32 bits now claims to be a Pentium 4.
        3.10.1 was wrongly claiming to be a CORE 2, which is SSSE3.
 
+* Preliminary support for OS X 10.11 (El Capitan) has been added.
+
 * ==================== TOOL CHANGES ====================
 
 * Memcheck: