drm/amdgpu: remove set but not used variable 'direct_poll' in vcn_v2_0.c

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/gpu/drm/amd/amdgpu/vcn_v2_0.c:1848:39: warning: variable ‘direct_poll’ set but not used [-Wunused-but-set-variable]

It is introduced by commit dd26858a ("drm/amdgpu:
implement initialization part on VCN2.0 for SRIOV"), but never used,
so remove it.
Reviewed-by: Christian König <christian.koenig@amd.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/vcn_v2_0.c

@@ -1845,7 +1845,6 @@ static int vcn_v2_0_start_sriov(struct amdgpu_device *adev)
 	uint32_t table_size = 0;
 	struct mmsch_v2_0_cmd_direct_write direct_wt = { {0} };
 	struct mmsch_v2_0_cmd_direct_read_modify_write direct_rd_mod_wt = { {0} };
-	struct mmsch_v2_0_cmd_direct_polling direct_poll = { {0} };
 	struct mmsch_v2_0_cmd_end end = { {0} };
 	struct mmsch_v2_0_init_header *header;
 	uint32_t *init_table = adev->virt.mm_table.cpu_addr;
@@ -1855,8 +1854,6 @@ static int vcn_v2_0_start_sriov(struct amdgpu_device *adev)
 	direct_wt.cmd_header.command_type = MMSCH_COMMAND__DIRECT_REG_WRITE;
 	direct_rd_mod_wt.cmd_header.command_type =
 		MMSCH_COMMAND__DIRECT_REG_READ_MODIFY_WRITE;
-	direct_poll.cmd_header.command_type =
-		MMSCH_COMMAND__DIRECT_REG_POLLING;
 	end.cmd_header.command_type = MMSCH_COMMAND__END;
 
 	if (header->vcn_table_offset == 0 && header->vcn_table_size == 0) {