target-tilegx: Add TILE-Gx building files

Add related configuration and make files for tilegx.
The target can now build, though not run anything.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <BLU436-SMTP1588E5A03AD5E94B07E988B9660@phx.gbl>
Signed-off-by: Richard Henderson <rth@twiddle.net>
diff --git a/configure b/configure
index d7c24cd..2225c39 100755
--- a/configure
+++ b/configure
@@ -5450,6 +5450,8 @@
   s390x)
     gdb_xml_files="s390x-core64.xml s390-acr.xml s390-fpr.xml s390-vx.xml s390-cr.xml"
   ;;
+  tilegx)
+  ;;
   tricore)
   ;;
   unicore32)