MEDIUM: global: remove dead code from nbproc/bind_proc removal

MEDIUM: global: remove dead code from nbproc/bind_proc removal

Lots of places iterating over nbproc or comparing with nbproc could be
simplified. Further, "bind-process" and "process" parsing that was
already limited to process 1 or "all" or "odd" resulted in a bind_proc
field that was either 0 or 1 during the init phase and later always 1.

All the checks for compatibilities were removed since it's not possible
anymore to run a frontend and a backend on different processes or to
have peers and stick-tables bound on different ones. This is the largest
part of this patch.

The bind_proc field was removed from both the proxy and the receiver
structs.

Since the "process" and "bind-process" directives are still parsed,
configs making use of correct values allowing process 1 will continue
to work.