[KConfig] Add RT_LWIP_RAW and RT_LWIP_USING_RT_MEM configuration for LWIP.

components/net/KConfig

@@ -65,6 +65,10 @@ config RT_USING_LWIP
         config RT_LWIP_TCP
             bool "TCP protocol"
             default y
+        
+        config RT_LWIP_RAW
+            bool "RAW protocol"
+            default n
 
         config RT_LWIP_PPP
             bool "PPP protocol"
@@ -78,6 +82,10 @@ config RT_USING_LWIP
             bool "PPPoS protocol"
             default n
 
+        config RT_LWIP_USING_RT_MEM
+            bool "Using RT-Thread Memory Management for LWIP"
+            default y
+        
         config RT_LWIP_PBUF_NUM
             int "the number of PBUF"
             default 16