[Bug target/64784] -march=native should be supported

[mwahab at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64784
Bug 64784 depends on bug 64783, which changed state.

Bug 64783 Summary: -march=armv8.1-a should be supported
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64783

           What    |Removed                     |Added
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             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED