net: phy: ncsi: depend on NET

PHY_NCSI enables drivers/net/phy/ncsi.c which calls net_loop() and
net_set_timeout_handler(). That's the legacy NET stack (as opposed to
NET_LWIP). Therefore add the dependency to Kconfig.

Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
Reviewed-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

drivers/net/phy/Kconfig

@@ -368,6 +368,7 @@ config PHY_FIXED
 
 config PHY_NCSI
 	bool "NC-SI based PHY"
+	depends on NET
 
 endif #PHYLIB