Merge of working DMC-11 device from Rob Jarratt.

pdp11_dmc.c
	- Fixed DMA bug which wrote data into the wrong simulated memory address.
	- Fixed incoming IP address checking.

pdp11_io_lib.c
	- Added the DMC device to the autoconfigure device table

vax780_defs.h
	- Added comment for DMC11
3 files changed