USB: ehci: minor cleanups

Minor cleanups to the EHCI code:  revision history is what source
code repositories should have.  Switch to a more standard way to
kick in verbose debugging -- don't be EHCI-specific.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>