a/a/c/arm920t/at91/reset.c: drop obsolete CONFIG_AT91RM9200_USART

The CONFIG_AT91RM9200_USART is an remnant of
18ed5e9550810e2fc5bf2c757aee47774609651c which deleted the
at91rm9200_usart driver.

Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
diff --git a/arch/arm/cpu/arm920t/at91/reset.c b/arch/arm/cpu/arm920t/at91/reset.c
index 4fa0f98..cd9c9f3 100644
--- a/arch/arm/cpu/arm920t/at91/reset.c
+++ b/arch/arm/cpu/arm920t/at91/reset.c
@@ -43,10 +43,6 @@
 void reset_cpu(ulong ignored)
 {
 	at91_st_t *st = (at91_st_t *) ATMEL_BASE_ST;
-#if defined(CONFIG_AT91RM9200_USART)
-	/*shutdown the console to avoid strange chars during reset */
-	serial_exit();
-#endif
 
 	board_reset();