Some chips provide both average and input power.  Previously
we just exposed average power, add a new query for input
power.

Example userspace:
https://github.com/Umio-Yasuno/libdrm-amdgpu-sys-rs/tree/input_powerReviewed-by: Yang Wang <kevinyang.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>