Linux 3.12 rc4

Hmm. rc4 has more new commits than rc3, which doesn't make me feel all
warm and fuzzy, but nothing major really stands out. More filesystem
upfates than normal at this stage, perhaps, but I suspect that is just
happenstance. We have cifs, xfs, btrfs, fuse and nilfs2 fixes here.

There's the usual driver updates too (mainly net and target this time
around), along with some generic networking changes too. And some arch
updates (arm, power, s+core, avr32).

But nothing scary, so go out and test.