drm/amd/pm: Use uploaded size for legacy custom PPTable

drm/amd/pm: Use uploaded size for legacy custom PPTable

The legacy powerplay path used to allocate hardcode_pp_table from
the original VBIOS PPTable size, copy only the uploaded bytes into it,
and keep soft_pp_table_size unchanged. If a custom PPTable is shorter
than the original table, later code can still treat the stale tail as
valid table data.

Treat the uploaded buffer as the complete custom PPTable: duplicate the
uploaded buffer directly, replace hardcode_pp_table atomically, and set
soft_pp_table_size to the uploaded size.

Signed-off-by: Yang Wang <kevinyang.wang@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>