Pull MD fixes from Shaohua Li:
"A few bug fixes for MD:
- Guoqing fixed a bug compiling md-cluster in kernel
- I fixed a potential deadlock in raid5-cache superblock write, a
hang in raid5 reshape resume and a race condition introduced in
rc4"
* tag 'md/4.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
raid5: fix a small race condition
md-cluster: make md-cluster also can work when compiled into kernel
raid5: guarantee enough stripes to avoid reshape hang
raid5-cache: fix a deadlock in superblock write