system: Start work on system abstraction layer.

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>
scripts: move the doxyfile and write doxy make target

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>
hal: Add system init functions

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>
system: Hook up memory allocation to system node

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>
system: Make kmalloc dependent of abstraction

All references to kalloc, kzalloc and free have been removed, to make
way for kmalloc.

In order to be able to plug in other memory allocation schemes, kmalloc
has been turned into a macro which references the abstraction layer.
In order to test this, we had to remove the references to the old
system.

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>
system: Add memory allocating documentation

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>