move definition of 'base addresses' from libcpu/powerpc to BSP code

[strauman]

• _IO_BASE, _ISA_MEM_BASE and PCI_DRAM_OFFSET are no longer defined by libcpu (powerpc/shared/include/io.h) but by the BSP (who is the only one to know the values)

• the affected BSP (shared/motorola) headers have been fixed in a separate "libbsp/powerpc/shared" patch (look for a PR with a slightly higher number than this one)

• the DEC 21140 driver (libchip/network/dec21140.c) has been fixed to use PCI_DRAM_OFFSET instead of PREP_PCI_DRAM_OFFSET. and PCI_MEM_BASE instead of PREP_ISA_MEM_BASE. PCI_MEM_BASE is to be defined by the BSP who is using this driver.

• the DEC driver also has been fixed to use the newer rtems_bsp_delay_in_bus_cycles() instead of the obsolete delay_in_bus_cycles().

NOTE: This patch should be used together with a related
patch (libbsp/powerpc/shared) which will have a PR number
slightly higher than this one...

Release:
RTEMS-ss-20020301

Environment:
target: powerpc-rtems

How-To-Repeat:
n.a.

[Joel Sherrill]

State-Changed-From-To: open->closed
State-Changed-Why: Patch applied.

[strauman]

libcpu_powerpc_io.diff