dbus-monitor: more details on file descriptors

dbus-monitor: more details on file descriptors

Print more details when receiving a file descriptor.

Before:
   unix fd 5

After:
   file descriptor
         inode: 1030
         type: char
   file descriptor
         inode: 295664
         type: socket
         address family: unknown (16)
   file descriptor
         inode: 295665
         type: socket
         address family: inet
         name 127.0.0.1 port 47723
         peer 127.0.0.1 port 22
   file descriptor
         inode: 295666
         type: socket
         address family: unix
         name @/tmp/d67s774Sws0pEra
   file descriptor
         inode: 295667
         type: socket
         address family: unix
         name @
         peer @

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=80603
Reviewed-by: Simon McVittie <simon.mcvittie@collabora.co.uk>