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Use --cobalt to link against libcobalt with no symbol wrapping,
referring to overriden POSIX routines by using __RT() or __COBALT()
qualifiers explicitly.

Use --posix to link against libcobalt with symbol wrapping.

By initializing the mutex or condvar on first access

The relevant code is statically built into the kernel, so there is no
point in preparing for modinfo to pull this documentation.

In theory, a Xenomai process on a different CPU might race with the
reclaim code if it starts then exits while the global resources are
being released on the current CPU. Unlikely, but possible though.

Queue the global resources to be reclaimed from the exiting process to
a local stash under nklock protection before cleaning them up.

We have different lifetimes for Cobalt-managed POSIX objects such as
mutexes and condvars, and Cobalt maintains dynamically allocated
resources for them.

Some POSIX objects are embedded into the session header for protecting
sysgroups, and serializing allocation ops on the shared
heap. Therefore, they must survive until the last process detaches
from the anon session.

Most other POSIX objects stored into the shared heap become virtually
stale when the application exits and should be reclaimed
automatically, so that we don't end up leaking kernel resources as
processes come and go into the anon session.

For the sake of simplicity, Cobalt reclaims shared POSIX objects upon
exit of their respective creator, assuming that a multi-process
application requires all involved processes to be present at any time,
including the one which has initialized the resources.

By using separate, per-process heaps for each instance of the anon
session, we make sure that all POSIX resources can be reclaimed safely
by Cobalt for any given session, upon application exit.