Documentation: embargoed-hardware-issues.rst: Remove myself

I'm no longer able to perform this role since I left IBM.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8734czh8yg.fsf@mpe.ellerman.id.au


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>