ARM: introduce arch_early_init_r()

Introduce arch_early_init_r() function, which can be useful for doing
early initialization after relocation has happened.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>

arch/arm/include/asm/u-boot-arm.h

@@ -52,6 +52,7 @@ void	cpu_init_cp15(void);
 /* cpu/.../arch/cpu.c */
 int	arch_cpu_init(void);
 int	arch_misc_init(void);
+int	arch_early_init_r(void);
 
 /* board/.../... */
 int	board_init(void);

arch/arm/lib/board.c

@@ -500,6 +500,10 @@ void board_init_r(gd_t *id, ulong dest_addr)
 	malloc_start = dest_addr - TOTAL_MALLOC_LEN;
 	mem_malloc_init (malloc_start, TOTAL_MALLOC_LEN);
 
+#ifdef CONFIG_ARCH_EARLY_INIT_R
+	arch_early_init_r();
+#endif
+
 #if !defined(CONFIG_SYS_NO_FLASH)
 	puts("Flash: ");