[PATCH] USB: usbcore: don't check the device's power source

The choose_configuration() routine contains code the determine the
device's power source, so that configurations requiring external power
can be ruled out if the device is running on bus power.  Unfortunately
it turns out that some devices have errors in their config descriptors
and other devices don't like the GET_DEVICE_STATUS request.

Since that information wasn't used for anything else, this patch (as673)
removes the code, leaving only a comment.  It fixes bugzilla entry
#6448.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>