common: Update comment to show progress

This file doesn't include any declarations anymore but it does include
other headers. Update the header comment to mention this.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/common.h b/include/common.h
index 388d98a..0ef8505 100644
--- a/include/common.h
+++ b/include/common.h
@@ -2,9 +2,8 @@
 /*
  * Common header file for U-Boot
  *
- * This file still includes quite a bit of stuff that should be in separate
- * headers. Please think before adding more things.
- * Patches to remove things are welcome.
+ * This file still includes quite a few headers that should be included
+ * individually as needed. Patches to remove things are welcome.
  *
  * (C) Copyright 2000-2009
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.