[PATCH, RFC 2/3] ARM: gemini: remove platform support

The gemini platform has not seen any updates from its
maintainer since 2010, and has no defconfig file, which
has lead to bitrot in a number of places:

* System restart has been broken for a long time despite
 repeated attempts from Russell to get the obvious
 fix at least acknowledged by someone who can test it.
* The platform still uses mach/gpio.h, which has been
 deprecated for some time, and since Kconfig does not
 select NEED_MACH_GPIO_H, it actually failed to build
 because of this.
* A change to asm/io.h introduced a number of compiler
 warnings for gemini specific code that confuses
 physical and virtual addresses.

This removes gemini support entirely under the assumption
that nobody uses it on mainline kernels. Of course, if
there are still active users out there, they should let
us know so we can put support back in and get it better
tested.

I am using the Gemini platform for an OpenWRT port to the
NAS IB4220 B and I am maintaing patches for the complete
support, including network, disk and and USB.

A few days ago I ported everything already to 3.7.1 (pretty
much the same changes like I saw in RFC 1/3)

I am willing to become maintainer for this platform and
would apreciate to keep it in the mainline. There is also
no problem with the tests, as I have several devices and
more than 100 users using this kernel.

Thanks
Tobias