Do not use system libraries as dependencies

Make will find system libraries for -lusb, -ldbus... That is not wanted.
Libraries are in linux-devkit directory.  Make could be pointed to
this directory, but as it is binary anyway, I do not really care.
Add missing mkdir for program archive
Add check for imagemagick

Provide a hint to user if it is not installed.
Add check for mkimage

Provide a hint to user if it is not installed.
Update README.md for build system change