Modified to support the change to the network ioctl signature changes.  Also add support for new ioctl to setup PHY event notifications.

Finishes the ioctl definition to subscribe to PHY events. Revamp network ioctl signature to support arguments other than struct mii_ioctl_data.

Add support for an ioctl that can be used to notify an application when there is a change in the network status signalled by a PHY interrupt

libc/time/lib_localtime.c is much closer to NuttX coding style. libc/time/private.h removed; incorporated into lib_localtime.c

When reading the system timer, don't read a struct timespec, convert it to a fake tick count, then back to a timespec.  Remove CLOCK_ACTIVETIME.. it is non-standard, unused, and gets in the way of changes like this

Tickless Stuff:  Back out the risky timer operations when the ready-to-run list is modified.  That is unsafe.  An ugly workaround is just to keep an interval timer going all of the time with a minimum duration equal to the timeslice interval.