pxa: move serial driver to drivers/serial

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/include/configs/delta.h b/include/configs/delta.h
index bacbd90..e7186e8 100644
--- a/include/configs/delta.h
+++ b/include/configs/delta.h
@@ -82,6 +82,7 @@
 /*
  * select serial console configuration
  */
+#define CONFIG_PXA_SERIAL
 #define CONFIG_FFUART		1
 
 /* allow to overwrite serial and ethaddr */