drm/amdgpu: Cleanup shift coding style

Improves the coding style by updating bit-shift
operations in the amdgpu_jpeg.c driver file.
It ensures consistency and avoids potential issues
by explicitly using 1U and 1ULL for unsigned
and unsigned long long shifts in all relevant instances.

Signed-off-by: Advait Dhamorikar <advaitdhamorikar@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>