More bugs

[utzoo!decvax!pur-ee!cincy!chris]

Found some more tonite:
	in attempting to make diff, there is a bad flag, -d2, to 
	the loader. Apparently this means something on the VAX,
	but not on an 11.
	also in diff, there is a call to a macro N_BADMAG, which
	I found in the VAX a.out.h, but not in the supplied one.
	in compiling login, the number of entries  in the struct
	ltchars in the source and in <sys/ioctl.h> do not agree.

		Chris Kent