cmd: net: wget: fix Kconfig dependency

The wget command uses TCP, but fails to select PROT_TCP in Kconfig.
Instead it selects the non-existing symbol TCP. Fix the typo.

Signed-off-by: Michael Walle <michael@walle.cc>
diff --git a/cmd/Kconfig b/cmd/Kconfig
index d93731f..b2d7598 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1814,7 +1814,7 @@
 
 config CMD_WGET
 	bool "wget"
-	select TCP
+	select PROT_TCP
 	help
 	  wget is a simple command to download kernel, or other files,
 	  from a http server over TCP.