[Bug target/89456] target attribute doesn't work well with -mXXX

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89456

--- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> ---
Created attachment 45853
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=45853&action=edit
A patch