The CL #39795 (https://codereview.chromium.org/2345593003 ) added MultiReturnSelect_f32/MultiReturnSelect_f64 tests.
  Because those tests need 2 float point return registers and x87 only has 1 FP return register, Those tests failed at x87 port.

  This CL skips MultiReturnSelect_f32/MultiReturnSelect_f64 tests for x87.

BUG=

Review-Url: https://codereview.chromium.org/2405743002
Cr-Commit-Position: refs/heads/master@{#40113}