powerpc: Fix stackprotector detection for non-glibc toolchains

[Michael Ellerman]

On Fri, 2018-10-12 at 22:58:32 UTC, Michael Ellerman wrote:
> If GCC is not built with glibc support then we must explicitly tell it
> which register to use for TLS mode stack protector, otherwise it will
> error out and the cc-option check will fail.
> 
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
> Reviewed-by: Christophe Leroy <christophe.leroy at c-s.fr>

Applied to powerpc next.

https://git.kernel.org/powerpc/c/bf6cbd0c87f30d0e4401be91a8161c

cheers