wireless/ieee80211:  Add BSD license information to all files (except the Broadcom files -- need to revisit those).

wiress/ieee80211: Broadcom network driver needs to register as an ieee802.11 driver, not an Ethernet driver.

net: network drver now retains Ethernet MAC address in a union so that other link layer addresses may be used in a MULTILINK environment.

clock: Add new type ssystime_t for relative 64-bit ticks, change ticks<->time conversion functions to use ssystime_t

Add clock_resynchronize for better synchronization of CLOCK_REALTIME and CLOCK_MONOTONIC to match RTC after resume from low-power state.

Add up_rtc_getdatetime_with_subseconds under CONFIG_ARCH_HAVE_RTC_SUBSECONDS to allow initializing (and resynchronizing) system clock with subseconds accuracy RTC.

Move net/iob to drivers/iob so that the I/O buffering feature can be available to other drivers when networking is disabled.