firmware: Remove VbLockDevice() VbLockDevice() would be inconvenient to port to 64-byte NV storage records because it doesn't take VbSharedData flags or a vb2_context. So, just have depthcharge call vbnv_write() directly (as it does in other places in fastboot.c) and get rid of this API. BUG=chromium:789276 BRANCH=none TEST=make runtests CQ-DEPEND=CL:944183 Change-Id: I2aeaecf7f929cd1a1ebd1f6850d0dd96c6fabb49 Signed-off-by: Randall Spangler <[email protected]> Reviewed-on: https://chromium-review.googlesource.com/944243 Reviewed-by: Furquan Shaikh <[email protected]>