huddly-updater: enable triple stream by default

Huddly GO camera can be configured to single, dual and triple stream
modes. For use in CfM, we need it to always be in triple stream mode.
This is needed for latest CfM feature changes.

BUG=b:112251234
TEST=Locally verified by running huddly-updater --prep. Stream mode
changed to triple as expected.

Change-Id: I25db12f5172b015bd9bb97d1c379b0c50020d554
Reviewed-on: https://chromium-review.googlesource.com/1169178
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Dirk Kaeding <dkaeding@chromium.org>
Reviewed-by: Zhongze Hu <frankhu@google.com>
diff --git a/src/main.cc b/src/main.cc
index 4e2e6bc..faba2d0 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -226,7 +226,7 @@
 }
 
 bool ConfigStreamMode() {
-  const huddly::StreamMode kMode = huddly::StreamMode::DUAL;
+  const huddly::StreamMode kMode = huddly::StreamMode::TRIPLE;
   huddly::MinicamDevice minidev(huddly::kVendorId, huddly::kProductIdApp);
   std::string err_msg;
   if (!minidev.Setup(&err_msg)) {