Adjust perf charts for v2 suites job name style.

New suites use release/R21 instead of release-R21.

BUG=chromium-os:31846
TEST=http://truty.i/croschart/server/chart?testkey=platform_BootPerfServer,seconds_kernel_to_startup,seconds_kernel_to_startup_done,seconds_kernel_to_x_started,seconds_kernel_to_chrome_exec,seconds_kernel_to_chrome_main,seconds_kernel_to_login,seconds_kernel_to_network&interval=4,week&board=x86-alex-r21&system=alex&width=1200&height=800&updatecache=true

Change-Id: If974f3184b5791494f7b2280f3dc8715cf3031d3
Reviewed-on: https://gerrit.chromium.org/gerrit/25415
Reviewed-by: Richard Barnette <jrbarnette@chromium.org>
Tested-by: Mike Truty <truty@chromium.org>
Commit-Ready: Mike Truty <truty@chromium.org>
2 files changed