Fix benchmark output label.
Fix benchmark output label.

Review URL: http://codereview.chromium.org/1456002

ionave/seismograph,coreboot/vboot,ccaapton/vboot_reference,marineam/seismograph,geekboxzone/mmallow_external_vboot_reference,geekboxzone/mmallow_external_vboot_reference,coreboot/vboot,ionave/seismograph,ccaapton/vboot_reference,marineam/seismograph,marineam/seismograph,acorn-marvell/vboot_reference,acorn-marvell/vboot_reference,ccaapton/vboot_reference,acorn-marvell/vboot_reference,marineam/seismograph,geekboxzone/mmallow_external_vboot_reference,ccaapton/vboot_reference,geekboxzone/mmallow_external_vboot_reference,acorn-marvell/vboot_reference,coreboot/vboot,ionave/seismograph,coreboot/vboot,coreboot/vboot,geekboxzone/mmallow_external_vboot_reference