This patch makes the monitor targets always register an execution control
task in GDB's thread list.  Needed to clean up inferior control, and
get rid of context switching.

I confirmed that it builds with x86_64-unknown-linux-gnu x h8300-elf cross,
and that it doesn't introduce any new warnings (this file is built without
-Werror).

As I said in my previous email, I don't even know how to test this, although
I don't except to be any fallout.

Does it look OK?  Can anyone instruct me how to test this; or do a test
spin for me; or claim that it looks ok, and we'll fix problems as
they arise?  :-)

-- 
Pedro Alves