smmuv2: Add ability to specify sid and cb numbers in a cdl file

[Apave24]

The main driver behind these changes are to allow the camkes tool to map specific stream id's to specific context banks for passthrough devices within a camkes vm application configuration. Related to seL4/camkes-vm#17

[lsf37]

The gitlint check is complaining about a too-long title (max 50 characters). Please shorten, but instead provide context and background/reasoning for the change in the body of the commit message instead.