This patch adds defconfig example to The Custom Boards How-To guide.
The command specified in this guide which runs configure script fails
if the defconfig file does not exists; the guide did not mention this
file at all.
If the file exists but is empty, the configure script fails and leaves
the system in a broken state which is somewhat difficult to deal with.
(Subsequent attempts to configure fail but so do attempts to distclean.)
To resolve this, this patch adds a minimal defconfig example which
should be sufficient for the configure script to do its work correctly.
Signed-off-by: Kerogit <kr.git@kerogit.eu>
c568a348f5