cmd: Remove <common.h> and add needed includes

Remove <common.h> from all "cmd/" files and when needed add
missing include files directly.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/cmd/io.c b/cmd/io.c
index 2de1111..617373d 100644
--- a/cmd/io.c
+++ b/cmd/io.c
@@ -7,9 +7,9 @@
  * IO space access commands.
  */
 
-#include <common.h>
 #include <command.h>
 #include <display_options.h>
+#include <vsprintf.h>
 #include <asm/io.h>
 
 /* Display values from last command */