common/board_r: Remove initr_serial wrapper

Remove the initr_serial->serial_initialize indirection and call
serial_initialize directly.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
diff --git a/common/board_r.c b/common/board_r.c
index d9307f0..3b2c6e0 100644
--- a/common/board_r.c
+++ b/common/board_r.c
@@ -187,12 +187,6 @@
 	return 0;
 }
 
-static int initr_serial(void)
-{
-	serial_initialize();
-	return 0;
-}
-
 #if defined(CONFIG_PPC) || defined(CONFIG_M68K) || defined(CONFIG_MIPS)
 static int initr_trap(void)
 {
@@ -714,7 +708,7 @@
 #endif
 	initr_dm_devices,
 	stdio_init_tables,
-	initr_serial,
+	serial_initialize,
 	initr_announce,
 #if CONFIG_IS_ENABLED(WDT)
 	initr_watchdog,