Add rxrz's exfat-nofuse driver

From http://github.com/rxrz/exfat-nofuse
Bring exfat up to 3e001ad

Using git merge -Xsubtree=fs/exfat -Xtheirs --squash
exFAT Kconfig and build bits
Merge branch '3.10/exfat' into 3.10/master