Changed GSM_API to GRGSM_API so gr_modtool created blocks don't have to be modified
diff --git a/include/grgsm/decryption/decryption.h b/include/grgsm/decryption/decryption.h
index 51328b1..b3a66e1 100644
--- a/include/grgsm/decryption/decryption.h
+++ b/include/grgsm/decryption/decryption.h
@@ -37,7 +37,7 @@
      * \ingroup gsm
      *
      */
-    class GSM_API decryption : virtual public gr::block
+    class GRGSM_API decryption : virtual public gr::block
     {
      public:
       typedef boost::shared_ptr<decryption> sptr;