mpc512x: Use in/out accessors for all registers

This is not only a cosmetic change as it fixes the real bug of board
reset not working with the ELDK 4.2 toolchain.

Signed-off-by: Detlev Zundel <dzu@denx.de>
diff --git a/cpu/mpc512x/serial.c b/cpu/mpc512x/serial.c
index 4fc4693..ec2f41b 100644
--- a/cpu/mpc512x/serial.c
+++ b/cpu/mpc512x/serial.c
@@ -1,5 +1,5 @@
 /*
- * (C) Copyright 2000 - 2009
+ * (C) Copyright 2000 - 2010
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  *
  * See file CREDITS for list of people who contributed to this
@@ -125,7 +125,7 @@
 	while (!(in_be16(&psc->psc_status) & PSC_SR_TXEMP))
 		;
 
-	psc->tfdata_8 = c;
+	out_8(&psc->tfdata_8, c);
 }
 
 void serial_putc_raw (const char c)
@@ -137,7 +137,7 @@
 	while (!(in_be16(&psc->psc_status) & PSC_SR_TXEMP))
 		;
 
-	psc->tfdata_8 = c;
+	out_8(&psc->tfdata_8, c);
 }
 
 
@@ -157,7 +157,7 @@
 	while (in_be32(&psc->rfstat) & PSC_FIFO_EMPTY)
 		;
 
-	return psc->rfdata_8;
+	return in_8(&psc->rfdata_8);
 }
 
 int serial_tstc (void)