i2c, dtt: move dtt_init () to board_init_r ()

it is not necessary to init the DTTs so early,
so move this init to board_init_r ().

Signed-off-by: Heiko Schocher <hs@denx.de>
diff --git a/lib_ppc/board.c b/lib_ppc/board.c
index 3bcfb45..6d29303 100644
--- a/lib_ppc/board.c
+++ b/lib_ppc/board.c
@@ -339,9 +339,6 @@
 #if defined(CONFIG_HARD_SPI)
 	init_func_spi,
 #endif
-#if defined(CONFIG_DTT)		/* Digital Thermometers and Thermostats */
-	dtt_init,
-#endif
 #ifdef CONFIG_POST
 	post_init_f,
 #endif
@@ -1072,6 +1069,9 @@
 
 	WATCHDOG_RESET ();
 
+#if defined(CONFIG_DTT)		/* Digital Thermometers and Thermostats */
+	dtt_init ();
+#endif
 #if defined(CONFIG_CMD_SCSI)
 	WATCHDOG_RESET ();
 	puts ("SCSI:  ");