UPSTREAM: arm64/efi: set PE/COFF section alignment to 4 KB

Position independent AArch64 code needs to be linked and loaded at the
same relative offset from a 4 KB boundary, or adrp/add and adrp/ldr
pairs will not work correctly. (This is how PC relative symbol
references with a 4 GB reach are emitted)

We need to declare this in the PE/COFF header, otherwise the PE/COFF
loader may load the Image and invoke the stub at an offset which
violates this rule.

Reviewed-by: Roy Franz <roy.franz@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

(cherry picked from commit ea6bc80d1819f307d98c6562c8ebb2c6c1297d47)
Signed-off-by: Tomasz Figa <tfiga@chromium.org>

Bug: 24475017

Change-Id: Iae24c73314b680bf3be1dd04bd38bfa1c3209dd2
Signed-off-by: Kees Cook <keescook@google.com>