scripts: fix tools override

The tools found by the new autostuff configure can contain arguments,
for example: grep -E

This needs separating the paths set for the Makfile from the paths
set for the scripts.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

 reporter_name="Ioannis E. Venetis"

 reporter_url="http://sourceware.org/ml/crossgcc/2011-05/msg00005.html"

 reporter_comment=""