split CPC45 board-specific IDE functions from cmd_ide.c

Move input_data() and friends to board/cpc45/ide.c, as overrides for weak
aliases in cmd_ide.c

note: checkpatch emits warnings about using volatile

Signed-off-by: Pavel Herrmann <morpheus.ibis@gmail.com>
diff --git a/board/cpc45/Makefile b/board/cpc45/Makefile
index 5c6b78f..ac1d174 100644
--- a/board/cpc45/Makefile
+++ b/board/cpc45/Makefile
@@ -25,7 +25,7 @@
 
 LIB	= $(obj)lib$(BOARD).o
 
-COBJS	= $(BOARD).o flash.o plx9030.o pd67290.o
+COBJS	= $(BOARD).o flash.o plx9030.o pd67290.o ide.o
 
 SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
 OBJS	:= $(addprefix $(obj),$(COBJS))