pldmfw: enable selected component update

This patch enables to update a selected component from PLDM image
containing multiple components.

Example usage:

struct pldmfw;
data.mode = PLDMFW_UPDATE_MODE_SINGLE_COMPONENT;
data.compontent_identifier = DRIVER_FW_MGMT_COMPONENT_ID;

Reviewed-by: Jacob Keller <[e-mail]>
Reviewed-by: Marcin Szycik <[e-mail]>
Reviewed-by: Przemek Kitszel <[e-mail]>
Signed-off-by: Konrad Knitter <[e-mail]>
Tested-by: Pucha Himasekhar Reddy <[e-mail]> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <[e-mail]>

include/linux/pldmfw.h

···
  * a pointer to their own data, used to implement the device specific
  * operations.
  */
+
+enum pldmfw_update_mode {
+	PLDMFW_UPDATE_MODE_FULL,
+	PLDMFW_UPDATE_MODE_SINGLE_COMPONENT,
+};
+
 struct pldmfw {
 	const struct pldmfw_ops *ops;
 	struct device *dev;
+	u16 component_identifier;
+	enum pldmfw_update_mode mode;
 };
 
 bool pldmfw_op_pci_match_record(struct pldmfw *context, struct pldmfw_record *record);

lib/pldmfw/pldmfw.c

···
 		component->component_data = data->fw->data + offset;
 		component->component_size = size;
 
+		if (data->context->mode == PLDMFW_UPDATE_MODE_SINGLE_COMPONENT &&
+		    data->context->component_identifier != component->identifier)
+			continue;
+
 		list_add_tail(&component->entry, &data->components);
 	}
+
+	if (data->context->mode == PLDMFW_UPDATE_MODE_SINGLE_COMPONENT &&
+	    list_empty(&data->components))
+		return -ENOENT;
 
 	header_crc_ptr = data->fw->data + data->offset;