sencha: disable starting a gdb server on the cheriot cpu

This fails but even when it worked the gdb service was not usable;
so just comment it out until we can resolve why it's broken.

Change-Id: I59f9b9a961f0b4be3d8bbf81672699546cc4663b

sencha.resc

diff --git a/sencha.resc b/sencha.resc
index efcabec..15fc07f 100644
--- a/sencha.resc
+++ b/sencha.resc
@@ -103,7 +103,8 @@
 # Kelvin programs.
 $gdb_port?=3333
 machine StartGdbServer $gdb_port false cpu0
-machine StartGdbServer $gdb_port false cpu1
+# TODO(sleffler) temp disable due to breakage
+#machine StartGdbServer $gdb_port false cpu1
 
 cpu0 IsHalted true
 cpu1 IsHalted true