Now that all the USB drivers have been audited, we can safely accept
devices that have noncompliant numbering for their interfaces or
altsettings.  This patch skips bad or duplicate descriptors, allows gaps
in the numbering, accepts more or fewer interfaces than bNumInterfaces,
and logs warnings describing all these things.  Also, the debugging log
messages have been improved by David Brownell.

This should please a sizeable group of users.