pxa: move serial driver to drivers/serial

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/include/configs/zylonite.h b/include/configs/zylonite.h
index 217636a..15c3708 100644
--- a/include/configs/zylonite.h
+++ b/include/configs/zylonite.h
@@ -72,6 +72,7 @@
 /*
  * select serial console configuration
  */
+#define CONFIG_PXA_SERIAL
 #define CONFIG_FFUART	       1
 
 /* allow to overwrite serial and ethaddr */