Update config files: re-enable twofish crypto support

Software twofish crypto support was disabled in several architectures
since openSUSE 10.3. For i386 and x86_64 it was on purpose, because
hardware-accelerated alternatives exist. However for all other
architectures it was by accident.

Re-enable software twofish crypto support in all configuration files,
to guarantee that at least one implementation is always available,
(bnc#871325).
Refresh patches.xen/xen3-patch-3.7 (fix another AR build issue).
Delete patches.arch/arm-omap3isp.patch.

superseded by 31036441d785359999e45bf410c778f64ffcab64
Update config files: disable CONFIG_I2C_SI470X

I2C access to the SI470X radio chip is only needed on embedded systems
so it makes no sense to enable it in most of our kernel configuration
files.
Update config files: disable all of Timberdale support

Timberdale is a companion chip for Atom CPUs in embedded in-car
infotainment systems. We don't need that in openSUSE, really.
Update x86_64 config files: disable CONFIG_SBC8360_WDT

The sbc8360 driver is for a Socket 370-based single-board computer,
so it's useless on x86-64.
- Refresh Xen patches (bnc#870874, bnc#871827).