openthread: enable SRP Client auto host address mode (#19981)

This commit enables "auto host address mode" in SRP client. When
enabled, host IPv6 addresses are automatically set by SRP client using
all the unicast addresses on Thread netif excluding the link-local and
mesh-local addresses. If there is no valid address, then Mesh Local
EID address is added. The SRP client will automatically re-register
when/if addresses on Thread netif are updated (e.g., new addresses are
added or existing addresses are removed).

src/platform/OpenThread/GenericThreadStackManagerImpl_OpenThread.cpp

@@ -190,7 +190,7 @@ void GenericThreadStackManagerImpl_OpenThread<ImplClass>::_OnPlatformEvent(const
 {
     if (event->Type == DeviceEventType::kThreadStateChange)
     {
-#if CHIP_DEVICE_CONFIG_ENABLE_THREAD_SRP_CLIENT
+#if CHIP_DEVICE_CONFIG_ENABLE_THREAD_SRP_CLIENT && (OPENTHREAD_API_VERSION < 218)
         if (event->ThreadStateChange.AddressChanged)
         {
             const otSrpClientHostInfo * hostInfo = otSrpClientGetHostInfo(Impl()->OTInstance());
@@ -2301,7 +2301,9 @@ template <class ImplClass>
 CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_SetupSrpHost(const char * aHostName)
 {
     CHIP_ERROR error = CHIP_NO_ERROR;
+#if OPENTHREAD_API_VERSION < 218
     Inet::IPAddress hostAddress;
+#endif
 
     VerifyOrReturnError(mSrpClient.mIsInitialized, CHIP_ERROR_WELL_UNINITIALIZED);
 
@@ -2316,15 +2318,21 @@ CHIP_ERROR GenericThreadStackManagerImpl_OpenThread<ImplClass>::_SetupSrpHost(co
         strcpy(mSrpClient.mHostName, aHostName);
         error = MapOpenThreadError(otSrpClientSetHostName(mOTInst, mSrpClient.mHostName));
         SuccessOrExit(error);
+
+#if OPENTHREAD_API_VERSION >= 218
+        error = MapOpenThreadError(otSrpClientEnableAutoHostAddress(mOTInst));
+#endif
     }
 
+#if OPENTHREAD_API_VERSION < 218
     // Check if device has any external IPv6 assigned. If not, host will be set without IPv6 addresses
     // and updated later on.
     if (ThreadStackMgr().GetExternalIPv6Address(hostAddress) == CHIP_NO_ERROR)
     {
         memcpy(&mSrpClient.mHostAddress.mFields.m32, hostAddress.Addr, sizeof(hostAddress.Addr));
         error = MapOpenThreadError(otSrpClientSetHostAddresses(mOTInst, &mSrpClient.mHostAddress, 1));
     }
+#endif
 
 exit:
     Impl()->UnlockThreadStack();