make sure we create map keys when we have all the typing information
make sure we create map keys when we have all the typing information

Map keys were being created too soon, and some typing information (such
as StackType in the case of ustack and kstack calls) could be missing in
some cases. If we wait until the final pass of the analizer to create
the keys, we have all the typing information.

Fixes: https://github.com/iovisor/bpftrace/issues/475

iovisor/bpftrace,iovisor/bpftrace,iovisor/bpftrace,iovisor/bpftrace