Drop sm70 from cu128 build targets to align with pytorch

Author: matthewdouglas

.github/scripts/build-cuda.sh

@@ -8,8 +8,8 @@ set -xeuo pipefail
 # By default, target Maxwell through Hopper.
 build_capability="50;52;60;61;70;75;80;86;89;90"
 
-# CUDA 12.8: Add sm100 and sm120; remove sm50 through sm61
-[[ "${cuda_version}" == 12.8.* ]] && build_capability="70;75;80;86;89;90;100;120"
+# CUDA 12.8: Add sm100 and sm120; remove < sm75 to align with PyTorch 2.7+cu128 minimum
+[[ "${cuda_version}" == 12.8.* ]] && build_capability="75;80;86;89;90;100;120"
 
 [[ "${build_os}" = windows-* ]] && python3 -m pip install ninja