tls: Depend upon INET not plain NET.

We refer to TCP et al. symbols so have to use INET as
the dependency.

   ERROR: "tcp_prot" [net/tls/tls.ko] undefined!
>> ERROR: "tcp_rate_check_app_limited" [net/tls/tls.ko] undefined!
   ERROR: "tcp_register_ulp" [net/tls/tls.ko] undefined!
   ERROR: "tcp_unregister_ulp" [net/tls/tls.ko] undefined!
   ERROR: "do_tcp_sendpages" [net/tls/tls.ko] undefined!

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/tls/Kconfig b/net/tls/Kconfig
index 61e5329..b13541f 100644
--- a/net/tls/Kconfig
+++ b/net/tls/Kconfig
@@ -3,7 +3,7 @@
 #
 config TLS
 	tristate "Transport Layer Security support"
-	depends on NET
+	depends on INET
 	default m
 	---help---
 	Enable kernel support for TLS protocol. This allows symmetric