The Windows Dev Kit 2023 (Volterra) has an UEFI implementation that maps
EfiLoaderData pages as non-executable. Map the kernel as EfiLoaderCode
to ensure that it can be executed.
With this change, FreeBSD boots to the mountroot prompt if
hw.pac.enable = 0 is set in loader.conf(5).
Revisions D37765, D37766, and D37767 are needed for this one to work.
Sponsored by: Berliner Linux User Group e.V.
Sponsored by: spline / FU-Berlin