Change gdb remote test support multi-request format.

The multi request-response test infrastructure support was adding
the optional request suffix iteration index as decimal but it needed
to be hex per spec.  This change fixes that.

llvm-svn: 209234

lldb/test/tools/lldb-gdbserver/lldbgdbserverutils.py

@@ -465,7 +465,7 @@ class MultiResponseGdbRemoteEntry(object):
 
         # Append the suffix as needed.
         if self._append_iteration_suffix:
-            payload += "%d" % self._iteration
+            payload += "%x" % self._iteration
 
         # Keep track of the iteration.
         self._iteration += 1