util/ectool.c: Fix resource leak
util/ectool.c: Fix resource leak

Found by Coverity Scan #141759.

BUG=none
BRANCH=none
TEST=none

Change-Id: I7b17330aa25a6d23c1a547829d6908931baa7891
Signed-off-by: Patrick Georgi <bc411205f21846a74924ee7b489c75617ec76078@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1789146
Tested-by: Patrick Georgi <bc411205f21846a74924ee7b489c75617ec76078@chromium.org>
Auto-Submit: Patrick Georgi <bc411205f21846a74924ee7b489c75617ec76078@chromium.org>
Commit-Queue: Patrick Georgi <bc411205f21846a74924ee7b489c75617ec76078@chromium.org>
Reviewed-by: Daisuke Nojiri <fd5f93af191bf7e8f73ea71cc3c0f66b41b1dd49@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec