px4_impl_nuttx:PX4 does not used compressed defconfigs nor configure.sh

   The new upstream nuttx defconfig format is compressed. This
   will not work well for board configs that are out of the
   upstream NuttX tree.

   The reconstitution step will not replace all the non default
   settings. I.E. CONFIG_ARCH_BOARD_PX4xxxx and will remove
   setting that are not defined from the config/KConfig. Like
   CONFIG_ARCH_BOARD_PX4xxxx=y.

   Also the configure script will fail if run without
   and intervening make distclean

   The only 2 steps from configure that re needed are
   Copying the defconfig to .config and Make.defs