A patch for RTEMS4.10.0 PowerPC heap space initialization

[Kate Feng]

Kate Feng wrote:
> Hi Joel,
>
>    There are bugs in RTEMS4.10.0 and its CVS for the PowerPC heap space
> allocation.  All PPC boards are limited to 32M bytes of memory space due
> to the change in RTEMS4.10 for its work space. The attached patch 
> fixed this.
> I consider that it is critical.  Thus, I will submit a PR.
>
>   Cheers,
>   Kate Feng
This is just a patch for the PowerPC port for your reference.  I do not know
how it will impact other ports since I do not have the boards.

Cheers,
Kate Feng