Pull irq fix from Thomas Gleixner:
"A small fix for the affinity spreading code.
It failed to handle situations where a single vector was requested
either due to only one CPU being available or vector exhaustion
causing only a single interrupt to be granted.
The fix is to simply remove the requirement in the affinity spreading
code for more than one interrupt being available"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/affinity: Create affinity mask for single vector