RFR: 8352980: Purge infrastructure for FP-to-bits interpreter intrinsics after 32-bit x86 removal

[Vladimir Kozlov]

On Wed, 26 Mar 2025 15:53:45 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> [JDK-8076373](https://bugs.openjdk.org/browse/JDK-8076373) added the infrastructure to implement `_intBitsToFloat`, `_floatToRawIntBits`, `_longBitsToDouble`, `_doubleToRawLongBits` intrinsics in template interpreters. That work was needed to support NaNs for 32-bit x86, and is no longer needed. The C1/C2 compiler intrinsics for these are still implemented and functional.
> 
> I did not do deep testing, because the removed code is actually dead.
> 
> Additional testing:
>  - [x] GHA checks for platform builds
>  - [x] Linux x86_64 server fastdebug, `tier1`

Good.

-------------

Marked as reviewed by kvn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/24259#pullrequestreview-2718346078