Enable testSvdSubsetByIndex on ROCm
Enable testSvdSubsetByIndex on ROCm for full range cases (start=0, end=128).
Actual subsetting is still TPU-only since subset_by_index is not implemented
for GPU.
Changes:
- svd_test.py: Add 'rocm' to @run_on_devices decorator
- Skip subset_by_index cases (non-full range) on ROCm with appropriate message
