ns: rename to __ns_ref

Make it easier to grep and rename to ns_count.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

init/version-timestamp.c

@@ -8,7 +8,7 @@
 #include <linux/utsname.h>
 
 struct uts_namespace init_uts_ns = {
-	.ns.count = REFCOUNT_INIT(2),
+	.ns.__ns_ref = REFCOUNT_INIT(2),
 	.name = {
 		.sysname	= UTS_SYSNAME,
 		.nodename	= UTS_NODENAME,