SEC, PEI_CORE and PEIM type modules generally execute in place from
memory that is not writable. This means that it is not generally
possible to use an entrypoint implementation that stores a dynamically
generated stack cookie into a global variable. For PEIMs in particular,
there may be other options, such as a DEPEX on the permanent memory PPI,
but the current dynamic implementations of the stack checking library
entrypoints for PEI_CORE and PEIM modules must not be used as-is.
So remove them, and update the readme accordingly.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
96cf70951f