The add expander still contains some expansion code that was required for the previou...

The add expander still contains some expansion code that was required for the previous prolog/epilog code...

The add expander still contains some expansion code that was required for the
previous prolog/epilog code, but which is no longer needed.  I also noticed
that the current version splits off immediates from frame addressing
instructions, which doesn't seem a good idea.  Avoiding this resulted in small
codesize improvements.

    gcc/
        * config/aarch64/aarch64.md (add<mode>3): Remove
        redundant code.  Don't split frame based additions.

From-SVN: r241790