Update base-foc to use rev. 47

[Dmitry Shubin]

Hello.

I've updated Makefile and a patchset to use the latest snapshot of 
Fiasco.OC. So far I've tested only foc_x86_32 and foc_x86_64 under qemu, 
but we should be able to test foc_panda and foc_imx53 builds as well soon.

The patch is available here on foc-r47 branch:
git://github.com/Ksys-labs/genode.git