[PATCH 3 of 3 chg-port] chg: use in-tree hg executable to start server for testing

[Yuya Nishihara]

# HG changeset patch
# User Yuya Nishihara <yuya at tcha.org>
# Date 1451792732 -32400
#      Sun Jan 03 12:45:32 2016 +0900
# Node ID 7391868f5e5caa478b470b047f9fdc01a5f8676b
# Parent  723afd2311ace1ea1bacbd43d0e93a0ee6625542
chg: use in-tree hg executable to start server for testing

diff --git a/contrib/chg/Makefile b/contrib/chg/Makefile
--- a/contrib/chg/Makefile
+++ b/contrib/chg/Makefile
@@ -1,4 +1,4 @@
-HG = hg
+HG = $(CURDIR)/../../hg
 
 TARGET = chg
 SRCS = chg.c hgclient.c util.c