Fix invalid read by adjusting request size

The recent changes in `libpldm`[1] introduced a modification in the
size definitions for PLDM requests. Specifically, the size for
`PLDM_SET_EVENT_RECEIVER_REQ_BYTES` was changed from 5 bytes to 3
bytes, with the addition of a new definition
`PLDM_SET_EVENT_RECEIVER_REQ_HEARTBEAT_BYTES` (2 bytes).

Previously, the event manager code used the
`PLDM_SET_EVENT_RECEIVER_REQ_BYTES` definition directly, which
accounted for 5 bytes. However, after the update in `libpldm`, the test
cases began failing when run under Valgrind due to invalid reads, as
the total request size was no longer correctly accounted for.

This commit resolves the issue by adjusting the size of the request in
the `setEventReceiver` method, using both the
`PLDM_SET_EVENT_RECEIVER_REQ_BYTES` and
`PLDM_SET_EVENT_RECEIVER_REQ_HEARTBEAT_BYTES` definitions to ensure the
proper size is used.

Tested by:
```bash
meson test -t 10 -C build --print-errorlogs --wrapper "valgrind --error-exitcode=1"
```

[1]: https://github.com/openbmc/libpldm/commit/8c43abb70aeadde39d99af2c1b6b5d4a1416fc47

Change-Id: Ieb86d764b0c60a79d0a7f0f92f60ddf8812e6e84
Signed-off-by: Manojkiran Eda <manojkiran.eda@gmail.com>
diff --git a/platform-mc/platform_manager.cpp b/platform-mc/platform_manager.cpp
index 1dd2cca..008fdf9 100644
--- a/platform-mc/platform_manager.cpp
+++ b/platform-mc/platform_manager.cpp
@@ -448,7 +448,8 @@
     pldm_tid_t tid, pldm_event_message_global_enable eventMessageGlobalEnable,
     pldm_transport_protocol_type protocolType, uint16_t heartbeatTimer)
 {
-    size_t requestBytes = PLDM_SET_EVENT_RECEIVER_REQ_BYTES;
+    size_t requestBytes = PLDM_SET_EVENT_RECEIVER_REQ_BYTES +
+                          PLDM_SET_EVENT_RECEIVER_REQ_HEARTBEAT_BYTES;
     /**
      * Ignore heartbeatTimer bytes when eventMessageGlobalEnable is not
      * ENABLE_ASYNC_KEEP_ALIVE