arm64: mvebu: Rename db-88f7040 files to armada-8k

This moves some of the Armada DB-88F7040 board specific files to a more
generic name: armada-8k. This is in preparation for the Armada-8k
support which will be added soon. And since both platforms share
most devices, lets also share most source files to not duplicate
the code here.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Nadav Haklai <nadavh@marvell.com>
Cc: Neta Zur Hershkovits <neta@marvell.com>
Cc: Kostya Porotchkin <kostap@marvell.com>
Cc: Omri Itach <omrii@marvell.com>
Cc: Igal Liberman <igall@marvell.com>
Cc: Haim Boot <hayim@marvell.com>
Cc: Hanna Hawa <hannah@marvell.com>

include/configs/mvebu_armada-8k.h

@@ -4,8 +4,8 @@
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
-#ifndef _CONFIG_MVEBU_DB_88F7040_H
-#define _CONFIG_MVEBU_DB_88F7040_H
+#ifndef _CONFIG_MVEBU_ARMADA_8K_H
+#define _CONFIG_MVEBU_ARMADA_8K_H
 
 /*
  * High Level Configuration Options (easy to change)
@@ -128,4 +128,4 @@
 #define CONFIG_CMD_PART
 #define CONFIG_PARTITION_UUIDS
 
-#endif /* _CONFIG_MVEBU_DB_88F7040_H */
+#endif /* _CONFIG_MVEBU_ARMADA_8K_H */