This patch adds sparc32 sun4m SMP ECC memory controller support.

Three files are attached:

The first is a diff to existing code.
The second is a diff for the new eccmemctl.c.
The third is the openboot outputs for the 3 systems that support this chip.

This patch is necessary for using sun openboot prom images because they
expect the device to be present and will fault when it's not there.

A prom node will need to be added to openbios for this chip.