Simplify the Makefile in the examples sub-folder

This is done so that it doesn't depend anymore on the old Makefile-based
build system.

Signed-off-by: Paul Cercueil <paul.cercueil@analog.com>
Drop the old Makefile-based build system

Signed-off-by: Paul Cercueil <paul.cercueil@analog.com>
Add preliminary support for building Debian packages

Signed-off-by: Paul Cercueil <paul.cercueil@analog.com>
Updated .gitignore

Signed-off-by: Paul Cercueil <paul.cercueil@analog.com>