block: Change module.h -> export.h in bsg-lib.c

This file isn't using full modular functionality, and hence
can be "downgraded" to just using the export.h header.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

block/bsg-lib.c

@@ -25,7 +25,7 @@
 #include <linux/delay.h>
 #include <linux/scatterlist.h>
 #include <linux/bsg-lib.h>
-#include <linux/module.h>
+#include <linux/export.h>
 #include <scsi/scsi_cmnd.h>
 
 /**