tools: remove absolute path of chmod for vfio setup
tools: remove absolute path of chmod for vfio setup

setup.sh uses /usr/bin/chmod, but depending on distribution, it is not always there.
For example, Ubuntu has /bin/chmod. Fix this by removing the absolute path, like it is
done e.g. with grep.

Signed-off-by: Andre Richter <956ec235f6e94c1f3c74e30ea1c55766e36abf3b@gmail.com>

phermansson/dpdk,phermansson/dpdk,phermansson/dpdk,phermansson/dpdk