drm/amd: Export DMCUB version to sysfs

For supported ASICs DMCU version is exported, but ASICs that support
DMCUB there is no information exported to sysfs.

Add an attribute for DMCUB.

Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Link: https://lore.kernel.org/r/20250527155942.476354-1-mario.limonciello@amd.com
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Author: superm1

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

@@ -765,6 +765,7 @@ FW_VERSION_ATTR(sdma_fw_version, 0444, sdma.instance[0].fw_version);
 FW_VERSION_ATTR(sdma2_fw_version, 0444, sdma.instance[1].fw_version);
 FW_VERSION_ATTR(vcn_fw_version, 0444, vcn.fw_version);
 FW_VERSION_ATTR(dmcu_fw_version, 0444, dm.dmcu_fw_version);
+FW_VERSION_ATTR(dmcub_fw_version, 0444, dm.dmcub_fw_version);
 FW_VERSION_ATTR(mes_fw_version, 0444, mes.sched_version & AMDGPU_MES_VERSION_MASK);
 FW_VERSION_ATTR(mes_kiq_fw_version, 0444, mes.kiq_version & AMDGPU_MES_VERSION_MASK);
 FW_VERSION_ATTR(pldm_fw_version, 0444, firmware.pldm_version);
@@ -780,9 +781,10 @@ static struct attribute *fw_attrs[] = {
 	&dev_attr_ta_ras_fw_version.attr, &dev_attr_ta_xgmi_fw_version.attr,
 	&dev_attr_smc_fw_version.attr, &dev_attr_sdma_fw_version.attr,
 	&dev_attr_sdma2_fw_version.attr, &dev_attr_vcn_fw_version.attr,
-	&dev_attr_dmcu_fw_version.attr, &dev_attr_imu_fw_version.attr,
-	&dev_attr_mes_fw_version.attr, &dev_attr_mes_kiq_fw_version.attr,
-	&dev_attr_pldm_fw_version.attr, NULL
+	&dev_attr_dmcu_fw_version.attr, &dev_attr_dmcub_fw_version.attr,
+	&dev_attr_imu_fw_version.attr, &dev_attr_mes_fw_version.attr,
+	&dev_attr_mes_kiq_fw_version.attr, &dev_attr_pldm_fw_version.attr,
+	NULL
 };
 
 #define to_dev_attr(x) container_of(x, struct device_attribute, attr)