trace_processor_shell: Fix linenoise missing argument

TBR: primiano@google.com
Change-Id: Iac102536bc3df7e4f53c3f0c1b12a675c902ab92
diff --git a/src/trace_processor/trace_processor_shell.cc b/src/trace_processor/trace_processor_shell.cc
index 70d4ee1..fd8af99 100644
--- a/src/trace_processor/trace_processor_shell.cc
+++ b/src/trace_processor/trace_processor_shell.cc
@@ -57,7 +57,7 @@
   linenoiseHistorySetMaxLen(1000);
 }
 
-void FreeLine(char*) {
+void FreeLine(char* line) {
   linenoiseHistoryAdd(line);
   linenoiseFree(line);
 }