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

Remove <common.h> from this driver directory and when needed
add missing include files directly.

Signed-off-by: Tom Rini <trini@konsulko.com>

drivers/ddr/imx/imx9/ddr_init.c

@@ -3,7 +3,6 @@
  * Copyright 2022 NXP
  */
 
-#include <common.h>
 #include <errno.h>
 #include <log.h>
 #include <asm/io.h>
@@ -11,6 +10,7 @@
 #include <asm/arch/clock.h>
 #include <asm/arch/sys_proto.h>
 #include <linux/delay.h>
+#include <linux/string.h>
 
 static unsigned int g_cdd_rr_max[4];
 static unsigned int g_cdd_rw_max[4];