USB: OHCI: avoid conflicting platform drivers

Like the EHCI driver, OHCI supports a large number of different platform
glue drivers by directly including them, which causes problems with
conflicting macro definitions in some cases. As more ARM architecture
specific back-ends are required to coexist in a single build, we should
split those out into separate drivers. Unfortunately, the infrastructure
for that is still under development, so to give us more time, this uses
a separate *_PLATFORM_DRIVER macro for each ARM specific OHCI backend,
just like we already do on PowerPC and some of the other ARM platforms.

In linux-3.10, only the SPEAr and CNS3xxx back-ends would actually conflict
without this patch, but over time we would get more of them, so this
is a way to avoid having to patch the driver every time it breaks. We
should still split out all back-ends into separate loadable modules,
but that work is only needed to improve code size and cleanliness after
this patch, not for correctness.

While we're here, this fixes the incorrectly sorted error path
for the OMAP1 and OMAP3 backends to ensure we always unregister
the exact set of drivers that were registered before erroring out.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>