Fix interaction with lspci >= 3.8.0

Starting from pciutils 3.8.0 (specifically, this commit), lspci no longer supports the 0x prefix in hexadecimal numbers with its -d option.

This PR removes the 0x that is currently passed to lspci to make the daemon compatible with those newer pciutils. It should not break compatibility with older versions, as the libc function strtol was used before 3.8.0, which takes an optional 0x prefix.

Probably fixes #41 (closed), as the symptoms match and the problem started around the time pciutils got this update.