RFR: 8291000: C2: Purge LoadPLocked and Store*Conditional nodes

[Aleksey Shipilev]

On Tue, 26 Jul 2022 07:13:01 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> The last uses for these nodes was the inline contiguous allocations. With [JDK-8290706](https://bugs.openjdk.org/browse/JDK-8290706), these nodes are not used anymore and can be cleaned up.
> 
> Testing:
>  - [x] Linux x86_64 fastdebug tier1
>  - [x] Linux x86_32 fastdebug tier1
>  - [x] Linux AArch64 fastdebug tier1
>  - [x] Linux x86_64 Zero build
>  - [x] Linux AArch64 cross-build
>  - [x] Linux ARM cross-build
>  - [x] Linux S390X cross-build
>  - [x] Linux PPC64 cross-build
>  - [x] Linux RISC-V cross-build

Thank you, I'll be integrating soon, if there are no objections.

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PR: https://git.openjdk.org/jdk/pull/9636