LaunchXL-TMS57004:  Add enough framework to support a complete build.  Mostly just empty files for now

Rename CONFIG_ARMV7M_MPU to CONFIG_ARM_MPU so that we can reuse the configuration settings for the ARMV7R MPU

SAMV71-XULT: module configuration.  Module cannot link with libc because it has out-of-range function calls

Add CONFIG_ARCH_BOARD_CUSTOM_DIR_RELPATH

Refresh all configurations that have Telnetd enabled; those configurations now also need the telnet driver

Remove CONFIG_NET_PINGADDRCONF.  This was a uIP way of assigning IP addresses, but is not standard and not a appropriate feature in general.

SAME70:  Initialization has to be done a little differently because the board has no 32.768KHz crystal installed