usb/host/: const data must use __initconst not __initdata

Init data marked const should be annotated with __initconst for
correctness and not __initdata.  This also fixes LTO builds that
otherwise fail with section mismatch errors.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>