USB: EHCI: make CONFIG_USB_EHCI_TT_NEWSCHED default to Y

This patch (as1382) changes the USB_EHCI_TT_NEWSCHED Kconfig option to
be non-experimental and to default to Y.  This option has existed for
a long time, and I have not heard any complaints concerning it.  By
contrast, several people have reported that their devices could be
made to work only by enabling the option.

The point of changing the default is to cause the option to be enabled
by distros that simply use the default settings for esoteric things
like this.

This change was motivated by Bugzilla #15649.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>