scripts: handle gcc and linux in dl_cleanup script

scripts: handle gcc and linux in dl_cleanup script

Handle gcc and linux with a special regex that set their progname with
their major version. This way every minor version can be cleared. The
build cleanup logic can be tweaked later to clean the entire toolchain
and target dir with a different gcc version.

Signed-off-by: Ansuel Smith <[email protected]>
[reformat commit message]
Signed-off-by: Paul Spooren <[email protected]>