drm/amdgpu: set the APU flag based on package type

Since currently APU and dGPU share the same pcie class
while gmc init needs the flag to set up correctly for upcomming
memory allocations

v2: call get_pkg_type in smuio 13_0_3 is enough (hawking)

Signed-off-by: Shiwu Zhang <shiwu.zhang@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>