Move environment files from common/ to env/

About a quarter of the files in common/ relate to the environment. It
seems better to put these into their own subdirectory and remove the
prefix.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/board/freescale/mx31ads/u-boot.lds b/board/freescale/mx31ads/u-boot.lds
index 8a4a8a2..71a63f1 100644
--- a/board/freescale/mx31ads/u-boot.lds
+++ b/board/freescale/mx31ads/u-boot.lds
@@ -30,7 +30,7 @@
 	  drivers/mtd/built-in.o		(.text*)
 
 	  . = DEFINED(env_offset) ? env_offset : .;
-	  common/env_embedded.o(.text*)
+	  env/embedded.o(.text*)
 
 	  *(.text*)
 	}