[PATCH] x86_64: Use the x86-64 level for purgatory

[Simon Horman]

On Thu, Apr 17, 2025 at 09:31:40AM +0100, Ross Lagerwall wrote:
> The compiler may be configured by default to use a newer
> microarchitecture level such as x86-64-v3. Set purgatory to compile
> using the baseline x86-64 level since the environment isn't set up
> correctly to use SSE and AVX instructions.  At the same time, be a bit
> paranoid and add some additional flags to ensure that the compiler
> doesn't use any such instructions.
> 
> Signed-off-by: Ross Lagerwall <ross.lagerwall at citrix.com>

Thanks Ross, applied for inclusion in v2.0.32.