[PATCH][AARCH64]Fix immediate alternative of movhf_aarch64 pattern.

[PATCH][AARCH64]Fix immediate alternative of movhf_aarch64 pattern.

gcc/

2018-03-12  Renlin Li  <renlin.li@arm.com>

    * config/aarch64/aarch64.md (movhf_aarch64): Fix mode argument to
    aarch64_output_scalar_simd_mov_immediate.

gcc/testsuite/

2018-03-12  Renlin Li  <renlin.li@arm.com>

    * gcc.target/aarch64/movi_hf.c: New.
    * gcc.target/aarch64/f16_mov_immediate_1.c: Update.
    * gcc.target/aarch64/f16_mov_immediate_2.c: Update.

From-SVN: r258459