cmd/llvmplugin: update merged test expectations

[zhouguangyuan0718]

Summary

• update the x86 GoObj indirect-call marker offset to the current call instruction start
• isolate the pointer-vector alloca failure fixture from the independent realigned-alloca rejection
• leave production statepoint and GoObj writer behavior unchanged

Production-semantics evidence

go tool objdump shows the x86 register- and memory-indirect CALL instructions at function offset 17, each carrying exactly [0:0]R_CALLIND. Their stack-growth calls remain direct R_CALL:runtime.morestack_noctxt relocations. The direct-call fixture has no R_CALLIND.

The pointer-vector fixture's previous <2 x ptr>, align 16 exceeded the GoObj x86 stack alignment and correctly reached the realigned-allocation diagnostic first. A <1 x ptr>, align 8 fixture has no independent alignment violation and reaches the intended unsupported pointer-vector diagnostic. Pointer-vector support is not expanded.

Validation

• ctest --test-dir pkg/goallc-llvmplugin --output-on-failure (48/48)
• focused x86/AArch64 indirect-call relocation tests
• focused pointer-alloca failure tests
• plugin-loaded opt -passes=verify for both affected inputs
• llc -verify-machineinstrs for x86_64 and AArch64 GoObj indirect-call codegen
• git diff --check

[zhouguangyuan0718]

Superseded by #43: both the X86 indirect-call offset expectation and the pointer-vector fixture alignment fix are already present on go1.27.master. Rebuilt the latest toolchain and confirmed the complete plugin CTest suite passes 48/48, so there is no remaining unique diff to merge.