drm/amd/pm: Use pointer type for typecheck()

drm/amd/pm: Use pointer type for typecheck()

typecheck creates local variables based on the type passed. That could
result in stack frame size warnings like below in certain configs:

drivers/gpu/drm/amd/amdgpu/../pm/swsmu/smu13/smu_v13_0_6_ppt.c:2885:1: error: the frame size of 8304 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]

Checking against the pointer type is sufficient for the purpose of
getting a diagnostic message during build time.

Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Palmer Dabbelt <palmer@dabbelt.com>
Tested-by: Palmer Dabbelt <palmer@dabbelt.com>
Link: https://lore.kernel.org/r/20250610212141.19445-1-palmer@dabbelt.com
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>