Changeset 62184317 in rtems for c/src/exec

Patch from Ralf Corsepius <corsepiu@…> to reorganize POSIX
directory in preparation for automake:

Here is a shell script which reorganizes some parts of the exec/posix
source tree.

This shell scripts moves include files below exec/posix to different
locations than now. It doesn't yet apply automake, but still use the old
autoconf configuration scheme. It doesn't influence the build scheme at
all (unless I corrupted something), only the location of the header
files is different, which would ease applying automake later.

The purpose of this shell script is to demonstrate the style of
structural changes I would like to see in rtems in near future to
prepare a smooth transition to automake. Then CC could pickup rtems'
header files from their location inside of the source tree in future,
instead of the build tree as it is done now.

In case you would accept this patch/script, there would be more similiar
ones to come.