Same change as https://github.com/systemd/systemd/pull/34583 but for
systemd-measure. Otherwise we end up with PCR policy digest mismatches
as systemd-stub will measure the full virtual size of the kernel image
after it has been loaded while systemd-measure will disregard the extra
size introduced by SizeOfImage.
While ideally the stub would only measure the data that's actually on
disk and not the uninitialized data introduced by VirtualSize > SizeOfRawData,
we want newer systemd-measure to work with older stubs so we have to fix
systemd-measure and can't fix this in the stub.
Daan De Meyer
0005411352