integrate support for static builds
integrate support for static builds

Add a STATIC knob to easily get static builds of all binaries.
We want this for the signer system.

We also need to fix the bmpblk utility to look up its libraries
via pkg-config.

BUG=chromium:447051
TEST=`make STATIC=1` works now
BRANCH=none

Change-Id: Icaef1f19f4618b0ce2b934735796749539081a02
Reviewed-on: https://chromium-review.googlesource.com/241041
Trybot-Ready: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>
Tested-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>
Reviewed-by: Bill Richardson <129945214b1d548d8e49b6c29c43094f8c78057f@google.com>
Commit-Queue: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>
Reviewed-by: Hung-Te Lin <8a7fce4940baad93a69f5073b383c85deed9d9c4@chromium.org>

geekboxzone/mmallow_external_vboot_reference,acorn-marvell/vboot_reference,coreboot/vboot,coreboot/vboot,acorn-marvell/vboot_reference,geekboxzone/mmallow_external_vboot_reference,acorn-marvell/vboot_reference,coreboot/vboot,geekboxzone/mmallow_external_vboot_reference,acorn-marvell/vboot_reference,geekboxzone/mmallow_external_vboot_reference,geekboxzone/mmallow_external_vboot_reference,coreboot/vboot,coreboot/vboot