lwip: update open socket number.

modify default number from 4 to 10

components/lwip/Kconfig

@@ -19,7 +19,7 @@ config L2_TO_L3_COPY
 config LWIP_MAX_SOCKETS
     int "Max number of open sockets"
     range 1 16
-    default 4
+    default 10
     help
         Sockets take up a certain amount of memory, and allowing fewer
         sockets to be open at the same time conserves memory. Specify