Roll src/third_party/cros_system_api/ 9b9ccf7ac..61297bd64 (2 commits)

https://chromium.googlesource.com/chromiumos/platform2/system_api.git/+log/9b9ccf7ac88a..61297bd64bfd

$ git log 9b9ccf7ac..61297bd64 --date=short --no-merges --format='%ad %ae %s'
2019-10-02 yusukes system_api: Add cpus field to StartArcVm proto
2019-07-02 cylai system_api: compile attestation_ca.proto to golang

Created with:
  roll-dep src/third_party/cros_system_api

BUG=b:142144019,b:139752657
TEST=try

Change-Id: Ib5721ae0d5c0403dfac5880ec04bef4030444389
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1841897
Commit-Queue: Yusuke Sato <yusukes@chromium.org>
Commit-Queue: Yury Khmel <khmel@chromium.org>
Auto-Submit: Yusuke Sato <yusukes@chromium.org>
Reviewed-by: Yury Khmel <khmel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703108}

DEPS

@@ -877,7 +877,7 @@ deps = {
 
   # For Linux and Chromium OS.
   'src/third_party/cros_system_api': {
-      'url': Var('chromium_git') + '/chromiumos/platform2/system_api.git' + '@' + '9b9ccf7ac88ac67a2fe88bf9beeb0b07cf163d76',
+      'url': Var('chromium_git') + '/chromiumos/platform2/system_api.git' + '@' + '61297bd64bfd78f9d4288ab44e28976b53f369f2',
       'condition': 'checkout_linux',
   },