lib: reduce the use of module.h wherever possible

For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include.  Fix up any implicit
include dependencies that were being masked by module.h along
the way.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/lib/ratelimit.c b/lib/ratelimit.c
index c96d500..40e03ea 100644
--- a/lib/ratelimit.c
+++ b/lib/ratelimit.c
@@ -11,7 +11,7 @@
 
 #include <linux/ratelimit.h>
 #include <linux/jiffies.h>
-#include <linux/module.h>
+#include <linux/export.h>
 
 /*
  * __ratelimit - rate limiting