[riscv-port] RFR: 8278531: riscv: Remove duplicate code bitset_to_fregs

[Fei Yang]

On Fri, 10 Dec 2021 01:18:58 GMT, Feilong Jiang <fjiang at openjdk.org> wrote:

> After [JDK-8278337](https://bugs.openjdk.java.net/browse/JDK-8278337), the definition of `bitset_to_fregs` is just same as `bitset_to_regs`.
> 
> Hotspot and jdk tier1 passed on the unmatched board. All tests were tested without new failures.

Looks good.

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Marked as reviewed by fyang (Lead).

PR: https://git.openjdk.java.net/riscv-port/pull/28