ARM: at91: spl: add spl_early_init for sama5d2 platforms

The dm root node is needed early in the spl to allow the timer to be
used.  This change calls spl_early_init to initialize the dm root node.
Signed-off-by: NGreg Gallagher <greg@embeddedgreg.com>

arch/arm/mach-at91/spl_atmel.c

@@ -103,6 +103,13 @@ void board_init_f(ulong dummy)
 {
 	int ret;
 
+	if (IS_ENABLED(CONFIG_OF_CONTROL)) {
+		ret = spl_early_init();
+		if (ret) {
+			debug("spl_early_init() failed: %d\n", ret);
+			hang();
+		}
+	}
 	switch_to_main_crystal_osc();
 
 #ifdef CONFIG_SAMA5D2