The Octeon OHCI is now supported by the ohci-platform driver, and
USB_OCTEON_OHCI is marked as deprecated.  However, it is currently
still necessary to enable it in order to select
USB_OHCI_BIG_ENDIAN_MMIO.  Make CPU_CAVIUM_OCTEON select that as well,
so that USB_OCTEON_OHCI is really obsolete.

The old ohci-octeon and ehci-octeon drivers also only enabled big-endian
MMIO in case the CPU was big-endian.  Make the selections of
USB_EHCI_BIG_ENDIAN_MMIO and USB_OHCI_BIG_ENDIAN_MMIO conditional, to
match this.

Fixes: 2193dda5 ("USB: host: Remove ehci-octeon and ohci-octeon drivers")
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: linux-mips@linux-mips.org
Cc: David Daney <david.daney@cavium.com>
Cc: Chandrakala Chavva <cchavva@caviumnetworks.com>
Cc: Paul Martin <paul.martin@codethink.co.uk>
Patchwork: https://patchwork.linux-mips.org/patch/10178/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>