[Bug target/88952] The asm operator modifiers for rs6000 should be documented like they are for x86

[christopher.leonard at abaco dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88952

--- Comment #13 from Christopher Leonard <christopher.leonard at abaco dot com> ---
(In reply to Segher Boessenkool from comment #12)
> the oldest GCC still supported is GCC 7.

Apologies if it was not clear, but I am just reporting the issue for posterity
and it was not easy for me to check on a newer version at the time.

If you are wondering why people use old versions of GCC, my usecase is working
on a codebase where consistent output is desirable over new features or
bugfixes, going back to when 4.x was new.