RFR: 8353219: RISC-V: Fix client builds after JDK-8345298

[Robbin Ehn]

On Sat, 29 Mar 2025 02:01:17 GMT, Fei Yang <fyang at openjdk.org> wrote:

> Hi, please review this trivial change fixing a client build issue.
> The definitions of both `generate_float16ToFloat()` and `generate_floatToFloat16()` should be moved out of `COMPILER2_OR_JVMCI` macro scope. Testing: client builds fine on linux-riscv64 with this change.

Thanks!

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Marked as reviewed by rehn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/24307#pullrequestreview-2728341092