pxa: move serial driver to drivers/serial

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/include/configs/xaeniax.h b/include/configs/xaeniax.h
index 1632d29..83883f6 100644
--- a/include/configs/xaeniax.h
+++ b/include/configs/xaeniax.h
@@ -55,6 +55,7 @@
 /*
  * select serial console configuration
  */
+#define CONFIG_PXA_SERIAL
 #define CONFIG_BTUART	       1       /* we use BTUART on XAENIAX */