Detect clang version, instead of assuming default one
Detect clang version, instead of assuming default one

Change-Id: I559fe4251169f489d89e30b3576f8da08fb0941b

veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi,veritas-shine/minix3-rpi