docs-rst: add inter-document cross references

Add cross references for the development process documents
that were converted to ReST:
	Documentation/SubmitChecklist
	Documentation/SubmittingDrivers
	Documentation/SubmittingPatches
	Documentation/development-process/development-process.rst
	Documentation/stable_kernel_rules.txt

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>