[PATCH] powerpc/lib/sstep: Fix count leading zeros instructions

[David Laight]

From: naveen.n.rao at linux.vnet.ibm.com
> Sent: 09 October 2017 15:48
...
> This is about the behavior of the gcc builtin being undefined, rather
> than the actual cpu instruction itself.

I'd have hoped that the ggc builtin just generated the expected cpu instruction.
So is only undefined because it is very cpu dependant.

More problematic here would be any cpu flag register settings.
eg: x86 would set the 'Z' flag for zero input.

	David