libpldm: Implement encode/decode for GetBIOSAttributeCurrentValueByHandle

The GetBIOSAttributeCurrentValueByHandle command is used to get the
current value of the BIOS attribute by AttributeNameHandle.
The spec of GetBIOSAttributeCurrentValueByHandle command refers to
DSP0247_1.0.0: 8.8.

Signed-off-by: Adair Li <lichao.lc01@inspur.com>
Change-Id: Ic87408b0c02fd686033907f197130543ed7515c5
diff --git a/libpldm/bios.h b/libpldm/bios.h
index 64ee683..d405706 100644
--- a/libpldm/bios.h
+++ b/libpldm/bios.h
@@ -351,6 +351,37 @@
 
 /** @brief Decode GetBIOSAttributeCurrentValueByHandle request packet
  *
+ *  @param[in] instance_id - Message's instance id
+ *  @param[in] transfer_handle - Handle to identify a BIOS attribute transfer
+ *  @param[in] transfer_op_flag - Flag to indicate the start of a multipart
+ *                                 transfer
+ *  @param[in] attribute_handle - Handle to identify the BIOS attribute
+ *  @param[out] msg - Message will be written to this
+ *  @return pldm_completion_codes
+ */
+int encode_get_bios_attribute_current_value_by_handle_req(
+    uint8_t instance_id, uint32_t transfer_handle, uint8_t transfer_op_flag,
+    uint16_t attribute_handle, struct pldm_msg *msg);
+
+/** @brief Decode GetBIOSAttributeCurrentValueByHandle response packet
+ *
+ *  @param[in] msg - Response message
+ *  @param[in] payload_length - Length of response message payload
+ *  @param[out] completion_code - PLDM completion code
+ *  @param[out] next_transfer_handle - handle to identify the next portion of
+ * the transfer
+ *  @param[out] transfer_flag - To indicate what part of the transfer this
+ *                             response represents
+ *  @param[out] attribute_data - contains current value of attribute
+ *  @return pldm_completion_codes
+ */
+int decode_get_bios_attribute_current_value_by_handle_resp(
+    const struct pldm_msg *msg, size_t payload_length, uint8_t *completion_code,
+    uint32_t *next_transfer_handle, uint8_t *transfer_flag,
+    struct variable_field *attribute_data);
+
+/** @brief Decode GetBIOSAttributeCurrentValueByHandle request packet
+ *
  *  @param[in] msg - Request message
  *  @param[in] payload_length - Length of request message payload
  *  @param[out] transfer_handle - Handle to identify a BIOS table transfer