[TIRX] Bind parallel loops to GPU threads before VerifyMemory

[zhils]

VerifyMemory on GPU targets treats direct accesses outside thread environments as illegal. In the ScatterValue CUDA lowering path, topi.scatter_elements emits ForKind::kParallel loops without explicit thread bindings, which triggers false host-memory access failures (e.g. "Did you forget to bind?") during TIR verification.

This change adds a new tirx pass (BindParallelLoopsToThreads) and inserts it before VerifyMemory in the s_tir pipelines (including adreno). The pass rewrites parallel loops into blockIdx.x/threadIdx.x thread-extent regions, substitutes loop vars with global thread indices, and adds bounds checks for non-divisible extents. This preserves correctness while ensuring GPU kernels pass memory verification for this path.

[gemini-code-assist]

Code Review

This pull request introduces the BindParallelLoopsToThreads pass, which converts ForKind::kParallel loops into GPU block and thread bindings, and integrates this pass into the S-TIR pipelines. Additionally, it provides a configuration option to allow unsupported host compilers for NVCC on Windows and adds a functional test for scatter operations on CUDA. Review feedback identifies a critical issue regarding the handling of nested parallel loops which could lead to invalid GPU register bindings, an inconsistency in GPU device type definitions between files, and a minor code redundancy in the loop variable substitution logic.