tracetool: allow ) in trace output string

Be greedy in matching the trailing "\)*" pattern.  Otherwise, all the
text in the trace string up to the last closed parenthesis is taken as
part of the prototype.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

scripts/tracetool

@@ -51,7 +51,7 @@ get_args()
 {
     local args
     args=${1#*\(}
-    args=${args%\)*}
+    args=${args%%\)*}
     echo "$args"
 }