[PATCH] ppc32: Allow ERPN for early serial to depend on CPU type

The PowerPC 440SPe supports up to 16 GB of RAM, and therefore its IO registers
are at 0x4_xxxx_xxxx instead of being at 0x1_xxxx_xxxx like most other PPC 440
chips.  To allow for this, this patch moves the definition of the ERPN used
for mapping UART0 from being hard-coded in the head_44x.S assembly code to
being defined in ibm44x.h.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Matt Porter <mporter@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>