Add a case for is_fp_pair in StackTransferRecipe, when moving registers.
This is similar to the is_gp_pair case, but we only need to check the
low fp register, and move both low and high if the low fp register is
different.

Bug: v8:9909
Change-Id: I02f72f6390a1b2802afce5e91ed227b749d838ae
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2013223
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65923}