Blackfin Serial Driver: Remove BI status for known_good_char

Signed-off-by: Sonic Zhang <[e-mail]>
Signed-off-by: Bryan Wu <[e-mail]>
Signed-off-by: Alan Cox <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/serial/bfin_5xx.c

···
 			return;
 
  known_good_char:
+			status &= ~BI;
 			anomaly_start.tv_sec = 0;
 		}
 	}