Use path found by salt.utils.which
Use path found by salt.utils.which

I ran into this problem running `salt-ssh '*' test.ping` with a
XenServer 6.5 node as the target. Even though the `lspci` and
`dmidecode` (after I installed it) commands are found by
`salt.utils.which`, because they're not actually in the `$PATH`, they
fail to execute.

saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt