[Go] Emit GoObj entry and stack-growth maps

[zhouguangyuan0718]

Summary

• make split-stack growth the default for GoObj Go functions, with go-nosplit as the sole exception
• emit one zero-byte EntryArgsStackMapID record for every GoObj Go function, including nosplit functions
• emit a real root-free StackGrowthStatepointID only at runtime.morestack* for split functions
• adapt Machine StackMaps in core AsmPrinter/GoObj emission and reject inconsistent entry, nosplit, or rooted stack-growth records
• retain target-specific argument homes and fixed-frame fail-closed checks

Stack position

This is 3/4 in the runtime LLVM support stack.

Depends on #73 (and transitively #77).
Next/final layer: #76, X86 ABI0/ABIInternal boundary repair.

Testing

The reordered stack is tree-identical to the previously green #71 integration head. The integrated stack passed the LLVM GoObj suite, GoALLC plugin tests, Go TestLLVM, and mixed runtime.test.

[github-actions]

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[zhouguangyuan0718]

按最新评审结论，这一层已经完整折叠进 #73：入口 ArgsPointerMaps 与 split/nosplit 解耦，morestack 不再制造 statepoint，GoObj 通过 CFG 派生的 PCSP 在入口栈深度恢复 map 0。#76 也已直接 rebase 到 #73，因此关闭这个过时的中间层。