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/swiotlb.c b/lib/swiotlb.c
index 058935e..9c6c937 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -20,7 +20,7 @@
 #include <linux/cache.h>
 #include <linux/dma-mapping.h>
 #include <linux/mm.h>
-#include <linux/module.h>
+#include <linux/export.h>
 #include <linux/spinlock.h>
 #include <linux/string.h>
 #include <linux/swiotlb.h>