ARM: convert arch_fixup_memory_node to a generic FDT fixup function

Some architecture needs extra device tree setup. Instead of adding
yet another hook, convert arch_fixup_memory_node to be a generic
FDT fixup function.

[maz: collapsed 3 patches into one, rewrote commit message]

Signed-off-by: Ma Haijun <mahaijuns@gmail.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
diff --git a/arch/arm/lib/bootm-fdt.c b/arch/arm/lib/bootm-fdt.c
index e40691d..8394e15 100644
--- a/arch/arm/lib/bootm-fdt.c
+++ b/arch/arm/lib/bootm-fdt.c
@@ -20,7 +20,7 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
-int arch_fixup_memory_node(void *blob)
+int arch_fixup_fdt(void *blob)
 {
 	bd_t *bd = gd->bd;
 	int bank;
diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
index a08586f..178e8fb 100644
--- a/arch/arm/lib/bootm.c
+++ b/arch/arm/lib/bootm.c
@@ -359,7 +359,7 @@
 	if (images->ft_addr) {
 		off = fdt_path_offset(images->ft_addr, "/memory");
 		if (off < 0) {
-			if (arch_fixup_memory_node(images->ft_addr))
+			if (arch_fixup_fdt(images->ft_addr))
 				puts("## WARNING: fixup memory failed!\n");
 		}
 	}