fix long-standing debug-name confusion
The calls to IR1-CONVERT-LAMBDA-BODY with the a VARARGS-ENTRY and
HAIRY-ARG-PROCESSOR debug-names were no such things.
These calls produces the actual lambda for the main body of the function,
and as such should have the original source-name and debug-name.
As proof of the pudding, we previously failed to detect several known
function that are recursive but aren't marked as such in the DEFKNOWNs. With
this that changes, so fix the DEFKNOWNs.