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/checksum.c b/lib/checksum.c
index 8df2f91..12dceb2 100644
--- a/lib/checksum.c
+++ b/lib/checksum.c
@@ -32,7 +32,7 @@
 /* Revised by Kenneth Albanowski for m68knommu. Basic problem: unaligned access
  kills, so most of the assembly has to go. */
 
-#include <linux/module.h>
+#include <linux/export.h>
 #include <net/checksum.h>
 
 #include <asm/byteorder.h>