drm/amdkfd: Add SVM API support capability bits

drm/amdkfd: Add SVM API support capability bits

SVMAPISupported property added to HSA_CAPABILITY, the value match
HSA_CAPABILITY defined in Thunk spec:

SVMAPISupported: it will not be supported on older kernels that don't
have HMM or on systems with GFXv8 or older GPUs without support for
48-bit virtual addresses.

CoherentHostAccess property added to HSA_MEMORYPROPERTY, the value match
HSA_MEMORYPROPERTY defined in Thunk spec:

CoherentHostAccess: whether or not device memory can be coherently
accessed by the host CPU.

Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>