scripts: fix stripping in finalisation step

The heuristic to find shell script is deficient. Fix it.

Reported-by: Kyle Grieb <grieb.kyle@gmail.com>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

reporter_name="Alexander BIGGA"

reporter_url="http://sourceware.org/ml/crossgcc/2008-06/msg00031.html"

reporter_comment=""