Missing namespaces in tofino back end.

[fruffy]

A lot of the files in the tofino backend have namespace BFN but it should be namespace P4:BFN. A lot of the files (in particular in bf-asm) do not have any namespace at all. This should be fixed.

[Vineet1101]

@fruffy taking on this task. anything else you would like to tell

[fruffy]

This is a fairly straightforward task but you will have to edit many files. You may also run into compilation problems because of the namespace change, which may need to be fix. Usually the change is simple, but it can be tedious.

Another thing: Anything like P4::IR::... or similar within the namespaces can be simplified to IR:: after this change.

[Vineet1101]

ok i will start working on this

[ChrisDodd]

A lot of the files (in particular in bf-asm) do not have any namespace at all. This should be fixed.

Why? bfas is a standalone executable, not a library, so there's no point to using namespaces other than obfuscation.

[fruffy]

Why? bfas is a standalone executable, not a library, so there's no point to using namespaces other than obfuscation.

Similar reasoning as #4707 (comment). If you want to use the assembler as library this could become an issue (although it's unlikely that will be the case for now).

bfas is also not completely standalone, it does call into lib a fair bit. As part of the compiler it probably makes sense to encapsulate the code in the P4 namespace.