cmd_sign: drop an unnecessary include
cmd_sign: drop an unnecessary include

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BRANCH=none
BUG=none
TEST='make futil' still succeeds

Change-Id: Ied3cd13f05ea19091abb6752fd23e7bf9fa562fb
Signed-off-by: Vadim Bendebury <5515d6d2d0829cbe0dd0dcf2094aaded06d58514@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/3120001
Reviewed-by: Daisuke Nojiri <fd5f93af191bf7e8f73ea71cc3c0f66b41b1dd49@chromium.org>

coreboot/vboot,coreboot/vboot,coreboot/vboot,coreboot/vboot,coreboot/vboot