pxa: move serial driver to drivers/serial

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/include/configs/pxa255_idp.h b/include/configs/pxa255_idp.h
index 7485f72..2cae8ca 100644
--- a/include/configs/pxa255_idp.h
+++ b/include/configs/pxa255_idp.h
@@ -100,6 +100,7 @@
 /*
  * select serial console configuration
  */
+#define CONFIG_PXA_SERIAL
 #define CONFIG_FFUART	       1       /* we use FFUART on LUBBOCK */
 
 /* allow to overwrite serial and ethaddr */