usb: ohci-omap3: fix trivial typo

This is the ohci-omap3 driver, not ehci-omap. Correct this
obvious typo.

Signed-off-by: Keshava Munegowda <keshava_mgowda@ti.com>
Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>