Take SAI API lock while registering callback

Summary:
While trying to make sure no regression in Sai Replayer refactoring, noticed that a few SAI API calls are interleaving with each other. E.g.

```
memset(s_a,0,ATTR_SIZE*4096);
s_a[0].id=536870926;
rv=switch_api->set_switch_attribute(9840384019236126720U,s_a);
memset(s_a,0,ATTR_SIZE*4096);
s_a[0].id=120;
rv=switch_api->set_switch_attribute(9840384019236126720U,s_a);
rvCheck(rv,0,1952);

rvCheck(rv,0,1953);
```

This is because when we register callbacks, the call directly goes to SDK instead of going through Sai API.

To fix this, also take the SaiAPILock while registering callback.

Reviewed By: daiwei1983

Differential Revision:
D85834616

Privacy Context Container: L1297311

fbshipit-source-id: a52dc77be208ece5f80e3310b2642953c8ae493b

Author: Ron He

fboss/agent/hw/sai/api/SwitchApi.cpp

@@ -28,6 +28,7 @@ void SwitchApi::registerRxCallback(
   sai_attribute_t attr;
   attr.id = SAI_SWITCH_ATTR_PACKET_EVENT_NOTIFY;
   attr.value.ptr = (void*)rx_cb;
+  auto g{SaiApiLock::getInstance()->lock()};
   auto rv = _setAttribute(id, &attr);
   saiApiCheckError(
       rv,
@@ -43,6 +44,7 @@ void SwitchApi::registerPortStateChangeCallback(
   sai_attribute_t attr;
   attr.id = SAI_SWITCH_ATTR_PORT_STATE_CHANGE_NOTIFY;
   attr.value.ptr = (void*)port_state_change_cb;
+  auto g{SaiApiLock::getInstance()->lock()};
   auto rv = _setAttribute(id, &attr);
   saiApiCheckError(
       rv,
@@ -58,6 +60,7 @@ void SwitchApi::registerFdbEventCallback(
   sai_attribute_t attr;
   attr.id = SAI_SWITCH_ATTR_FDB_EVENT_NOTIFY;
   attr.value.ptr = (void*)fdb_event_cb;
+  auto g{SaiApiLock::getInstance()->lock()};
   auto rv = _setAttribute(id, &attr);
   saiApiCheckError(
       rv,
@@ -73,6 +76,7 @@ void SwitchApi::registerTamEventCallback(
   sai_attribute_t attr;
   attr.id = SAI_SWITCH_ATTR_TAM_EVENT_NOTIFY;
   attr.value.ptr = (void*)tam_event_cb;
+  auto g{SaiApiLock::getInstance()->lock()};
   auto rv = _setAttribute(id, &attr);
   saiLogError(
       rv,
@@ -89,6 +93,7 @@ void SwitchApi::registerQueuePfcDeadlockNotificationCallback(
   sai_attribute_t attr;
   attr.id = SAI_SWITCH_ATTR_QUEUE_PFC_DEADLOCK_NOTIFY;
   attr.value.ptr = (void*)queue_pfc_deadlock_notification_cb;
+  auto g{SaiApiLock::getInstance()->lock()};
   auto rv = _setAttribute(id, &attr);
   saiLogError(
       rv,
@@ -105,6 +110,7 @@ void SwitchApi::registerTxReadyStatusChangeCallback(
   sai_attribute_t attr;
   attr.id = SAI_SWITCH_ATTR_PORT_HOST_TX_READY_NOTIFY;
   attr.value.ptr = (void*)tx_ready_status_cb;
+  auto g{SaiApiLock::getInstance()->lock()};
   auto rv = _setAttribute(id, &attr);
   saiApiCheckError(
       rv,
@@ -123,6 +129,7 @@ void SwitchApi::registerSwitchAsicSdkHealthEventCallback(
   attr.id = SAI_SWITCH_ATTR_SWITCH_ASIC_SDK_HEALTH_EVENT_NOTIFY;
   attr.value.ptr = (void*)function;
 
+  auto g{SaiApiLock::getInstance()->lock()};
   auto rv = _setAttribute(id, &attr);
   saiApiCheckError(
       rv,
@@ -140,6 +147,8 @@ void SwitchApi::registerVendorSwitchEventNotifyCallback(
   sai_attribute_t attr;
   attr.id = SAI_SWITCH_ATTR_VENDOR_SWITCH_EVENT_NOTIFY;
   attr.value.ptr = (void*)event_notify_cb;
+
+  auto g{SaiApiLock::getInstance()->lock()};
   auto rv = _setAttribute(id, &attr);
   saiApiCheckError(
       rv,
@@ -156,6 +165,7 @@ void SwitchApi::registerSwitchHardResetNotifyCallback(
   sai_attribute_t attr;
   attr.id = SAI_SWITCH_ATTR_SWITCH_HARD_RESET_EVENT_NOTIFY;
   attr.value.ptr = event_notify_cb;
+  auto g{SaiApiLock::getInstance()->lock()};
   auto rv = _setAttribute(id, &attr);
   saiApiCheckError(
       rv,