Added Samsung's exfat source, modded by @rxrz @lqs and @dorimanx

for more details, visit:

http://opensource.samsung.com/reception/receptionSub.do?method=sub&sub=F&searchValue=exfat

and

https://github.com/dorimanx/exfat-nofuse
exfat_super: fix compatibility issue
Update defconfigs