hw/m68k: Use the IEC binary prefix definitions

It eases code review, unit is explicit.

Patch generated using:

  $ git grep -E '(1024|2048|4096|8192|(<<|>>).?(10|20|30))' hw/ include/hw/

and modified manually.
Signed-off-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NThomas Huth <thuth@tuxfamily.org>
Message-Id: <20180625124238.25339-18-f4bug@amsat.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

hw/m68k/mcf5208.c

@@ -6,6 +6,7 @@
  * This code is licensed under the GPL
  */
 #include "qemu/osdep.h"
+#include "qemu/units.h"
 #include "qemu/error-report.h"
 #include "qapi/error.h"
 #include "qemu-common.h"
@@ -241,7 +242,7 @@ static void mcf5208evb_init(MachineState *machine)
     memory_region_add_subregion(address_space_mem, 0x40000000, ram);
 
     /* Internal SRAM.  */
-    memory_region_init_ram(sram, NULL, "mcf5208.sram", 16384, &error_fatal);
+    memory_region_init_ram(sram, NULL, "mcf5208.sram", 16 * KiB, &error_fatal);
     memory_region_add_subregion(address_space_mem, 0x80000000, sram);
 
     /* Internal peripherals.  */