[Bug target/71733] ICE in vmx test cases with -mcpu=power9

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71733

--- Comment #5 from Peter Bergner <bergner at gcc dot gnu.org> ---
This patch bootstrapped and regtested with no regressions.  I'll submit it when
I get back from the long holiday weekend.