Fix(CUDA): add missing isk parameter to DeltaSpin force kernel GPU version

The CUDA GPU version of cal_force_nl_op for DeltaSpin was missing the
'isk' parameter that was present in the CPU version and ROCm/HIP version.
This caused a function signature mismatch during GPU compilation.

Added 'const int* isk' parameter to:
- source/source_pw/module_pwdft/kernels/force_op.h (GPU declaration)
- source/source_pw/module_pwdft/kernels/cuda/force_op.cu (GPU implementation)

This aligns the CUDA GPU implementation with the CPU and ROCm versions,
enabling correct spin channel handling in noncollinear DeltaSpin calculations.

Author: dyzheng

source/source_pw/module_pwdft/kernels/cuda/force_op.cu

@@ -545,6 +545,7 @@ void cal_force_nl_op<FPTYPE, base_device::DEVICE_GPU>::operator()(const base_dev
                                                                   const FPTYPE& tpiba,
                                                                   const FPTYPE* d_wg,
                                                                   const FPTYPE* lambda,
+                                                                  const int* isk,
                                                                   const std::complex<FPTYPE>* becp,
                                                                   const std::complex<FPTYPE>* dbecp,
                                                                   FPTYPE* force)

source/source_pw/module_pwdft/kernels/force_op.h

@@ -277,6 +277,7 @@ struct cal_force_nl_op<FPTYPE, base_device::DEVICE_GPU>
                     const FPTYPE& tpiba,
                     const FPTYPE* d_wg,
                     const FPTYPE* lambda,
+                    const int* isk,
                     const std::complex<FPTYPE>* becp,
                     const std::complex<FPTYPE>* dbecp,
                     FPTYPE* force);