Increase netlink uevent rcvbuf size to 16M

Increase size of the NETLINK_KOBJECT_UEVENT socket receive buffer to
16M.  Also, use SO_RCVBUFFORCE to override any limits set by
/proc/sys/net/core/rmem_max.

We had a couple of instances, where we lost critical uevent messages due
to receive buffer overflows.

Bug: 119933843
Change-Id: I6aab183aa0194e173f9175b47c6beb0835cf6675