3B2: Multiple bugfixes and improvements

- Allow 3 MB RAM configuration (previously only 1MB, 2MB, and 4MB
  configurations were allowed)
- Allow SCSI CIO card to be used under 3B2/400 emulation (previously
  it could only be used under 3B2/700 emulation)
- Improved CTC, PORTS, and SCSI diagnostic checks
- Fixed a bug in IDISK device that allowed impossible disk
  configurations

The last update is a breaking change that disables the HD161 disk
type by default, since real 3B2 hardware does not support it. The
disk type will still allowed in backward compatibility mode through
use of the "SET IDISK LARGE" command.

makefile

@@ -2129,7 +2129,7 @@ ATT3B2M400 = ${ATT3B2D}/3b2_cpu.c ${ATT3B2D}/3b2_sys.c \
     ${ATT3B2D}/3b2_if.c ${ATT3B2D}/3b2_id.c \
     ${ATT3B2D}/3b2_dmac.c ${ATT3B2D}/3b2_io.c \
     ${ATT3B2D}/3b2_ports.c ${ATT3B2D}/3b2_ctc.c \
-    ${ATT3B2D}/3b2_ni.c
+    ${ATT3B2D}/3b2_scsi.c ${ATT3B2D}/3b2_ni.c
 ATT3B2M400_OPT = -DUSE_INT64 -DUSE_ADDR64 -DREV2 -I ${ATT3B2D} ${NETWORK_OPT} ${AIO_CCDEFS}
 
 ATT3B2M700 = ${ATT3B2D}/3b2_cpu.c ${ATT3B2D}/3b2_sys.c \
@@ -2878,7 +2878,7 @@ endif
 
 ${BIN}3b2${EXE} : ${ATT3B2M400} ${SIM}
 	${MKDIRBIN}
-	${CC} ${ATT3B2M400} ${SIM} ${ATT3B2M400_OPT} ${CC_OUTSPEC} ${LDFLAGS}
+	${CC} ${ATT3B2M400} ${SCSI} ${SIM} ${ATT3B2M400_OPT} ${CC_OUTSPEC} ${LDFLAGS}
 ifeq (${WIN32},)
 	cp ${BIN}3b2${EXE} ${BIN}3b2-400${EXE}
 else