[Bug target/72853] gcc/testsuite/gcc.c-torture/execute/20021120-1.c generates incorrect stxssp op with -mcpu=power9

[meissner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72853

--- Comment #1 from Michael Meissner <meissner at gcc dot gnu.org> ---
I believe this is a duplicate of PR 72802 that Alan fixed on August 8th for
trunk (subversion id 239233), and backported to the gcc-6-branch (subversion id
239269)