USB: ohci-omap: handle other omap15xx chips

Sync up USB parts of the ohci-omap support in mainline with the OMAP tree.
This patch supports another first generation OMAP1 part: not just the
OMAP 1510 (and its catalog version, the OMAP 5910), but also OMAP 310.

From: Tony Lindgren <tony@atomide.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>