toolchain.defs: Remove absolute path

Avoid hard-coded absolute paths.
Assume gcc and ar will be found using $PATH.

Change-Id: Ie7bd7d262a56a20741c8b3e5c1d0d600d8a1b60d
Signed-off-by: Juro Bystricky <juro.bystricky@intel.com>
1 file changed