GraphBLAS: Avoid warning from Clang 17.

[mmuetzel]

Clang 17 emits more warnings (or errors) when it comes to incompatible pointer types.

_InterlockedCompareExchange is declared with long volatile * as the type of its first input argument
See: https://learn.microsoft.com/en-us/cpp/intrinsics/interlockedcompareexchange-intrinsic-functions?view=msvc-170

int32_t is int on Windows. While long and int have the same size on Windows (LLP64 data model), they are technically distinct types.

Avoid the compiler warning by casting to the pointer type expected by that function.

Without this change, clang-cl 17 emits warnings like the following:
https://github.com/DrTimothyAldenDavis/SuiteSparse/actions/runs/9404241025/job/25902701998#step:16:3057

[2990/5428] Building C object GraphBLAS\CMakeFiles\GraphBLAS.dir\Release\FactoryKernels\GB_AxB__band_band_uint32.c.obj
In file included from D:\a\SuiteSparse\SuiteSparse\GraphBLAS\FactoryKernels\GB_AxB__band_band_uint32.c:179:
In file included from D:\a\SuiteSparse\SuiteSparse\GraphBLAS\Source\mxm/template/GB_AxB_saxbit_template.c:240:
D:\a\SuiteSparse\SuiteSparse\GraphBLAS\Source\mxm\template/GB_AxB_saxbit_A_sparse_B_bitmap_template.c(402,33): warning: incompatible pointer types passing 'volatile int32_t *' (aka 'volatile int *') to parameter of type 'volatile long *' [-Wincompatible-pointer-types]
  402 |                                 GB_Z_ATOMIC_UPDATE_HX (i, t) ;    // C(i,j) += t
      |                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
D:\a\SuiteSparse\SuiteSparse\GraphBLAS\Source\mxm/include/GB_AxB_saxpy3_template.h(509,21): note: expanded from macro 'GB_Z_ATOMIC_UPDATE_HX'
  509 |             while (!GB_Z_ATOMIC_COMPARE_EXCHANGE (pz, zold, znew)) ;    \
      |                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
D:\a\SuiteSparse\SuiteSparse\GraphBLAS\Source\omp\include/GB_kernel_shared_definitions.h(58,16): note: expanded from macro 'GB_Z_ATOMIC_COMPARE_EXCHANGE'
   58 |                GB_ATOMIC_COMPARE_EXCHANGE_32(target, expected, desired)
      |                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
D:\a\SuiteSparse\SuiteSparse\GraphBLAS\Source\omp/include/GB_atomics.h(413,42): note: expanded from macro 'GB_ATOMIC_COMPARE_EXCHANGE_32'
  413 |             _InterlockedCompareExchange ((int32_t volatile *) (target),     \
      |                                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

(Side note: I'm unsure where to open PRs wrt GraphBLAS. I opted for this repository because there is CI here.)

[DrTimothyAldenDavis]

Thanks for the fix. Posting the PR here is fine; I'll sync it with the stand-alone repo.