docs: deprecate pasta network name

Since pasta is now considered a network mode using it as network name
causes a conflict. For now we will prefer the named network but in a
future major version bump we want to remove this and just use pasta(1).

The docs should reflect that this name is considered deprecated.

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

docs/source/markdown/options/network.md

@@ -74,3 +74,6 @@ Valid _mode_ values are:
     - **pasta:-T,5201**: enable forwarding of TCP port 5201 from container to
         host, using the loopback interface instead of the tap interface for improved
         performance
+
+    NOTE: For backward compatibility reasons, if you have a network named `pasta`,
+    Podman will use this instead of the pasta mode.

docs/source/markdown/podman-network-create.1.md

@@ -15,6 +15,9 @@ If no options are provided, Podman will assign a free subnet and name for your n
 
 Upon completion of creating the network, Podman will display the name of the newly added network.
 
+NOTE: The support for the network name pasta is deprecated and will be removed in the next major
+release because it is used as a special network mode in **podman run/create --network**.
+
 ## OPTIONS
 #### **--disable-dns**