Documentation: net: net.core.txrehash is not specific to listening sockets

The net.core.txrehash documentation mentions this knob is for listening
sockets only, while sk_rethink_txhash can be called on SYN and RTO
retransmits on all TCP sockets.

Remove the listening socket part.
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Documentation/admin-guide/sysctl/net.rst

@@ -386,8 +386,8 @@ Default : 0  (for compatibility reasons)
 txrehash
 --------
 
-Controls default hash rethink behaviour on listening socket when SO_TXREHASH
-option is set to SOCK_TXREHASH_DEFAULT (i. e. not overridden by setsockopt).
+Controls default hash rethink behaviour on socket when SO_TXREHASH option is set
+to SOCK_TXREHASH_DEFAULT (i. e. not overridden by setsockopt).
 
 If set to 1 (default), hash rethink is performed on listening socket.
 If set to 0, hash rethink is not performed.