ICMPv6:  Add logic to behave like a router (if so configured):  NuttX will not send the router advertisement message in response to any router solicitation messages.

ICMPv6 Auto-configuration:  If no router reponds to the Router Solicitation, claim the link local address by sending the Neighbor Advertisement and return success

Networking:  Break out Ethernet definitions into a separate file; add IPv6 multicast addresses as common globals, Ethernet drivers need to filter link-local, all nodes Ethernet address

Re-arrange condition logic from the last change to avoid having STM32-specific conditional logic outside of the STM32 sandbox.

STM32:  Add driver for STM32L162XX AES peripheral. Signed-off-by: Juha Niskanen <juha.niskanen@haltian.com>

ICMPv6:  Some initial bugfix from first tests of the ICMPv6 auto-configuration logic.  so far so good but a lot more testing is needed

Also remove spaces before and after paretheses to conform to coding standard.

Networking:  Add support for sending ICMPv6 Router Solicitation and receiving Router advertisement.  This is a part of the ICMPv6 auto-configuration logic is still still not complete

On my platform I have just 16-bit timer clocked at 32kHz. As result oneshot timer max delay is 2s. The patch adds limit of maximum ticks in sched_timer_start (nuttx/sched/sched/sched_timerexpiration.c). From Macs N.