mpl/gpu: fix conversions/comparisons between runtime/driver API enums

[nmnobre]

Pull Request Description

Fixes conversions and comparisons between different CUDA runtime and driver API enum types:

  CC       src/gpu/mpl_gpu_cuda.lo
../../../mpich/src/mpl/src/gpu/mpl_gpu_cuda.c: In function 'MPL_gpu_ipc_handle_create':
../../../mpich/src/mpl/src/gpu/mpl_gpu_cuda.c:146:9: warning: implicit conversion from 'CUresult' {aka 'enum cudaError_enum'} to 'cudaError_t' {aka 'enum cudaError'} [-Wenum-conversion]
  146 |     ret = cuPointerGetAttribute(&ipc_handle->id, CU_POINTER_ATTRIBUTE_BUFFER_ID, (CUdeviceptr) ptr);
      |         ^
In file included from ../../../mpich/src/mpl/src/gpu/mpl_gpu_cuda.c:9:
../../../mpich/src/mpl/src/gpu/mpl_gpu_cuda.c: In function 'MPL_gpu_get_buffer_id':
../../../mpich/src/mpl/src/gpu/mpl_gpu_cuda.c:200:16: warning: comparison between 'CUresult' {aka 'enum cudaError_enum'} and 'enum cudaError' [-Wenum-compare]
  200 |     assert(ret == cudaSuccess);
      |                ^~
../../../mpich/src/mpl/src/gpu/mpl_gpu_cuda.c: In function 'MPL_gpu_ipc_handle_is_valid':
../../../mpich/src/mpl/src/gpu/mpl_gpu_cuda.c:211:16: warning: comparison between 'CUresult' {aka 'enum cudaError_enum'} and 'enum cudaError' [-Wenum-compare]
  211 |     assert(ret == cudaSuccess);
      |                ^~

Also removes HI_ERR_CHECK(), currently only used to check the return value of hipMemGetAddressRange(), which is of type hipError_t, so should compare with hipSuccess instead:

In file included from ../../../mpich/src/mpl/include/mpl.h:9:
../../../mpich/src/mpl/src/gpu/mpl_gpu_hip.c: In function 'MPL_gpu_get_buffer_bounds':
../../../mpich/src/mpl/src/gpu/mpl_gpu_hip.c:12:46: warning: comparison between 'hipError_t' and 'enum <anonymous>' [-Wenum-compare]
   12 | #define HI_ERR_CHECK(ret) if (unlikely((ret) != HIP_SUCCESS)) goto fn_fail
      |                                              ^~
../../../mpich/src/mpl/include/mpl_base.h:81:42: note: in definition of macro 'unlikely'
   81 | #define unlikely(x_) __builtin_expect(!!(x_),0)
      |                                          ^~
../../../mpich/src/mpl/src/gpu/mpl_gpu_hip.c:448:5: note: in expansion of macro 'HI_ERR_CHECK'
  448 |     HI_ERR_CHECK(hiret);
      |     ^~~~~~~~~~~~

Plus an unused variable:

../../../mpich/src/mpl/src/gpu/mpl_gpu_hip.c: In function 'MPL_gpu_init':
../../../mpich/src/mpl/src/gpu/mpl_gpu_hip.c:358:17: warning: unused variable 'global_dev_id' [-Wunused-variable]
  358 |             int global_dev_id;
      |                 ^~~~~~~~~~~~~

[hzhou]

LGTM

[hzhou]

test:mpich/ch4/gpu