DO NOT MERGE - Disable IPv6 RS/RA processing in dhcpcd.

Disable IPv6 RS/RA processing in dhcpcd, because:

1. It doesn't make sense to run IPv6 autoconfiguration both in
   the kernel and in dhcpcd.
2. The multinetwork code relies on the kernel IPv6 RS/RA
   implementation, including our patches to put RA-generated
   routes into per-network routing tables, so at best any
   autoconf routes created by dhcpcd will be ignored.
3. dhcpcd SEGVs when receiving certain router advertisements.

3) breaks DHCP renew on Ethernet, because dhcpcd crashes after
receiving an RA, and unlike wifi, the Ethernet code does not do
anything special to renew leases (it just relies on dhcpcd not
crashing). This is obviously a problem on molly.

Bug: 15268738
Change-Id: I05525cd9664ca381657473ac7e20c8ab86cea038
(cherry picked from commit 7c5edb63dfd4c6eecbbbba93003ee8c4112b17d0)
1 file changed