Make gcc happy and remove a couple of warnings

Remove the callbacks from gsm_network for now. A set of different
callbacks will be back. E.g. when the paging is completed, when the
Q.931 like call handling is there...

Remove var's or move them into #if 0, remove unused stuff that looks
like we do not need it anytime soon or #if 0 them, move stuff around.
diff --git a/src/debug.c b/src/debug.c
index ecd7be1..0a35dbc 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -77,7 +77,7 @@
 			if (strcasecmp(debug_info[i].name, category_token) == 0)
 				new_mask |= debug_info[i].number;
 		}
-	} while (category_token = strtok(NULL, ":"));
+	} while ((category_token = strtok(NULL, ":")));
 
 
 	free(mask);
@@ -120,3 +120,12 @@
 	fflush(outfd);
 }
 
+void hexdump(unsigned char *buf, int len)
+{
+	int i;
+	for (i = 0; i < len; i++) {
+		fprintf(stdout, "%02x ", buf[i]);
+	}
+	fprintf(stdout, "\n");
+}
+