These arrays are both keyed by CPU name and go into the same tablegenerated file. Merge them so we only need to store keys once.
This also removes a weird space saving quirk where we used the ProcDesc.size() to create to build an ArrayRef for ProcSched.
Macro function DBGFIELD(x) is only used from code generated by method EmitSchedClassTables. We can probably undef DBGFIELD after the call to EmitSchedClassTables and before the call to EmitProcessorModels.