[CP-2525] During Xapi startup, call PIF.refresh_all to update the MAC addresses and MTUs of all existing PIFs.
[CP-2525] During Xapi startup, call PIF.refresh_all to update the MAC addresses and MTUs of all existing PIFs.

Signed-off-by: Jonathan Knowles <47466d50a94574c6fb872a0e5feec104dcb68f29@eu.citrix.com>

simonjbeaumont/xcp-rrdd,johnelse/xcp-rrdd,koushikcgit/xcp-rrdd,koushikcgit/xcp-networkd,koushikcgit/xcp-rrdd,koushikcgit/xcp-rrdd,djs55/xcp-rrdd,robhoes/squeezed,koushikcgit/xcp-networkd,johnelse/xcp-rrdd,djs55/xcp-networkd,djs55/squeezed,sharady/xcp-networkd,simonjbeaumont/xcp-rrdd,djs55/xcp-rrdd,djs55/xcp-networkd,sharady/xcp-networkd