powerpc/book3s64: Always build for power4 or later

[Michael Ellerman]

On Fri, 2016-21-10 at 00:01:51 UTC, Michael Ellerman wrote:
> When we're not compiling for a specific CPU, ie. none of the
> CONFIG_POWERx_CPU options are set, and CONFIG_GENERIC_CPU *is* set, we
> currently don't pass any -mcpu option to the compiler. This means the
> compiler builds for a "generic" Power CPU.
> 
> But back in 2014 we dropped support for pre power4 CPUs in commit
> 468a33028edd ("powerpc: Drop support for pre-POWER4 cpus").
> 
> Given that, there's no point in building the kernel to run on pre power4
> cpus. So update the flags we pass to the compiler when
> CONFIG_GENERIC_CPU is set, to specify -mcpu=power4.
> 
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
> Acked-by: Balbir Singh <bsingharora at gmail.com>

Applied to powerpc next.

https://git.kernel.org/powerpc/c/3a849815a13695ad0e32f6f01c9054

cheers