ipv6: xfrm: use 64-bit timestamps

get_seconds() is deprecated because it can overflow on 32-bit
architectures.  For the xfrm_state->lastused member, we treat the data
as a 64-bit number already, so we just need to use the right accessor
that works on both 32-bit and 64-bit machines.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

include/net/xfrm.h

@@ -227,7 +227,7 @@ struct xfrm_state {
 	long		saved_tmo;
 
 	/* Last used time */
-	unsigned long		lastused;
+	time64_t		lastused;
 
 	struct page_frag xfrag;