Avoid zero-size VLA in cmd_dump_fmap.c
Avoid zero-size VLA in cmd_dump_fmap.c

Zero-size variable length arrays are undefined behavior. UBSan reported a
zero-size VLA in futility/cmd_dump_fmap.c when running tests. This
change fixes that by making sure the size of the VLA is at least 1.

BUG=chromium:1058086
TEST=FEATURES="test" USE="llvm-next ubsan" emerge -e --nodeps vboot_reference
BRANCH=none

Change-Id: I3c0eee0359668ce2e1ec3c0724f243788161fb13
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2103436
Tested-by: Bob Haarman <f8a7ee8d579bbbe50184d8b55a70a77dda6328a7@chromium.org>
Reviewed-by: Manoj Gupta <1d49d0f302d724a1dc5fc4d717d15418e9808ddd@chromium.org>
Reviewed-by: Julius Werner <4d12f06cff3725783b352157673a720bc67c4afe@chromium.org>
Commit-Queue: Manoj Gupta <1d49d0f302d724a1dc5fc4d717d15418e9808ddd@chromium.org>

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