drm/amdgpu: Remove unnecessary ras block support check

drm/amdgpu: Remove unnecessary ras block support check

[Why]:
   For special asic with mem ecc enabled but sram ecc
not enabled, some ras blocks can register their ras
configuration to ras list, but these ras blocks are not
enabled on .ras_enabled, so it can not get ras block
object using amdgpu_ras_get_ras_block.

[How]:
   Remove ras block support check. Even if the ras block
checked is not in the ras list, it will return a null
pointer and will have no effect.

Signed-off-by: YiPeng Chai <YiPeng.Chai@amd.com>
Reviewed-by: Tao Zhou <tao.zhou1@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>