Documentation: SubmittingDrivers: Resources

- Add additional location (Git) for the kernel master tree
- Add reference to Git Project

Signed-off-by: Abraham Arce <x0066660@ti.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>