buildsys: use single slash version of -print-whatever
buildsys: use single slash version of -print-whatever

The double slash variants are not documented (doc bug?) so better use
the single slash variants like we usually do.

Signed-off-by: Bernhard Reutner-Fischer <ce1ac9e9ad16abccd7821f371ad381197b4768ac@gmail.com>

joel-porquet/tsar-uclibc,joel-porquet/tsar-uclibc,joel-porquet/tsar-uclibc,joel-porquet/tsar-uclibc