drm/amdgpu: add mes resume when do gfx post soft reset

[why]
when gfx do soft reset, mes will also do reset, if mes is not
resumed when do recover from soft reset, mes is unable to respond
in later sequence

[how]
resume mes when do gfx post soft reset

Signed-off-by: Tong Liu01 <Tong.Liu01@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>