CVE-2024-56697: drm/amdgpu: Fix the memory allocation issue in amdgpu_discovery_get_nps_info()

In the Linux kernel, the following vulnerability has been resolved:

drm/amdgpu: Fix the memory allocation issue in amdgpudiscoverygetnpsinfo()

Fix two issues with memory allocation in amdgpudiscoverygetnpsinfo() for memranges:

- Add a check for allocation failure to avoid dereferencing a null pointer.

- As suggested by Christophe, use kvcalloc() for memory allocation, which checks for multiplication overflow.

Additionally, assign the output parameters npstype and rangecnt after the kvcalloc() call to prevent modifying the output parameters in case of an error return.