fix bug after commit 3dfa11b89e6a74e6857c11e3029b372c746d535f .change arfcn2downlink(a,b) to one argument in grgsm_decode and grgsm_capture and grgsm_channelize
diff --git a/apps/grgsm_decode b/apps/grgsm_decode
index 66ecae2..70cd284 100755
--- a/apps/grgsm_decode
+++ b/apps/grgsm_decode
@@ -354,12 +354,12 @@
                 parser.error("ARFCN is not valid in the specified band\n")
             else:
                 arfcn = options.arfcn
-                fc = grgsm.arfcn.arfcn2downlink(arfcn, options.band)
+                fc = grgsm.arfcn.arfcn2downlink(arfcn)
         else:
             arfcn = options.arfcn
             for band in grgsm.arfcn.get_bands():
                 if grgsm.arfcn.is_valid_arfcn(arfcn):
-                    fc = grgsm.arfcn.arfcn2downlink(arfcn, band)
+                    fc = grgsm.arfcn.arfcn2downlink(arfcn)
                     break
     elif options.fc:
         fc = options.fc