This patch fixes handling in case of link-local address compression. A
IPv6 link-local address is defined as fe80::/10 prefix which is also
what ipv6_addr_type checks for link-local addresses.

But IPHC compression for link-local addresses are for fe80::/64 types
only. This patch adds additional checks for zero padded bits in case of
link-local address compression to match on a fe80::/64 address only.
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>