Remove separate movtf pattern - Use an iterator for all FP modes.

Remove separate movtf pattern - Use an iterator for all FP modes.

movtf is unnecessary as a separate expander. Move this to be with
the standard scalar floating point expanders.

Achieved by adding a new iterator and then using the same.

Tested cross aarch64-none-elf and no regressions.

Rebased version from https://gcc.gnu.org/ml/gcc-patches/2015-09/msg00767.html

2015-09-10  Ramana Radhakrishnan  <ramana.radhakrishnan@arm.com>

	PR target/63304
        * config/aarch64/aarch.md (mov<mode>:GPF_F16): Use GPF_TF_F16.
        (movtf): Delete.
        * config/aarch64/iterators.md (GPF_TF_F16): New.
        (GPF_F16): Delete.

From-SVN: r227679