arm: actions: rename sysmap-s900 to sysmap-owl

Now that memory maps(for both S700 and S900 SoCs) can be managed using
a common file, rename sysmap-s900 to sysmap-owl to reflect the same.
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NAmit Singh Tomar <amittomer25@gmail.com>

arch/arm/mach-owl/Makefile

 # SPDX-License-Identifier:	GPL-2.0+
 
 obj-y += soc.o
-obj-y += sysmap-s900.o
+obj-$(CONFIG_ARM64) += sysmap-owl.o

arch/arm/mach-owl/sysmap-s900.c → arch/arm/mach-owl/sysmap-owl.c

 // SPDX-License-Identifier: GPL-2.0+
 /*
- * Actions Semi S900 Memory map
+ * Memory map for Actions Semi Owl series SoCs.
  *
  * Copyright (C) 2015 Actions Semi Co., Ltd.
  * Copyright (C) 2018 Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
@@ -9,7 +9,7 @@
 #include <common.h>
 #include <asm/armv8/mmu.h>
 
-static struct mm_region s900_mem_map[] = {
+static struct mm_region owl_mem_map[] = {
 	{
 		.virt = 0x0UL, /* DDR */
 		.phys = 0x0UL, /* DDR */
@@ -29,4 +29,4 @@ static struct mm_region s900_mem_map[] = {
 	}
 };
 
-struct mm_region *mem_map = s900_mem_map;
+struct mm_region *mem_map = owl_mem_map;