libpldm: fix the length bytes of get state sensor readings resp

Since the len of stateFields is variable(0x01-0x08), we only define
the min len for the get state sensor readings resp.

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: I105042a3c45e3b0a96b701c556e22579b56c1c03
diff --git a/libpldm/platform.h b/libpldm/platform.h
index 546712d..e1b5b23 100644
--- a/libpldm/platform.h
+++ b/libpldm/platform.h
@@ -18,7 +18,6 @@
 #define PLDM_GET_SENSOR_READING_REQ_BYTES 4
 /* Response lengths are inclusive of completion code */
 #define PLDM_SET_STATE_EFFECTER_STATES_RESP_BYTES 1
-#define PLDM_GET_STATE_SENSOR_READINGS_RESP_BYTES 34
 
 #define PLDM_SET_NUMERIC_EFFECTER_VALUE_RESP_BYTES 1
 #define PLDM_SET_NUMERIC_EFFECTER_VALUE_MIN_REQ_BYTES 4
@@ -28,6 +27,7 @@
 #define PLDM_GET_PDR_MIN_RESP_BYTES 12
 #define PLDM_GET_NUMERIC_EFFECTER_VALUE_MIN_RESP_BYTES 5
 #define PLDM_GET_SENSOR_READING_MIN_RESP_BYTES 8
+#define PLDM_GET_STATE_SENSOR_READINGS_MIN_RESP_BYTES 2
 
 /* Minimum length for PLDM PlatformEventMessage request */
 #define PLDM_PLATFORM_EVENT_MESSAGE_MIN_REQ_BYTES 3