Wrap the call to VERIFY_INTERFACE and add the parsing of the support
vectors.
v2: use a packed struct for handling the output of ACPI calls, hides
ugly pointer arithmetics (Lee, Chun-Yi <jlee@suse.com>).
v3: fix radeon_atif_parse_functions handling (Alex Deucher)
Signed-off-by: NLuca Tettamanti <kronos.it@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>