pw_rpc: Update docs to support concurrent calls

This restriction was removed by the support for current
calls added in afaacb6.

Change-Id: Ia06c72f413772c31aa4e1ada9cc19765abf84310
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/110991
Commit-Queue: Auto-Submit <auto-submit@pigweed.google.com.iam.gserviceaccount.com>
Reviewed-by: Wyatt Hepler <hepler@google.com>
Pigweed-Auto-Submit: Taylor Cramer <cramertj@google.com>
diff --git a/pw_rpc/docs.rst b/pw_rpc/docs.rst
index 4744668..e9b8de3 100644
--- a/pw_rpc/docs.rst
+++ b/pw_rpc/docs.rst
@@ -68,13 +68,6 @@
 packet with the RPC's status. The client may terminate an ongoing RPC by
 cancelling it.
 
-``pw_rpc`` supports only one RPC invocation per service/method/channel. If a
-client calls an ongoing RPC on the same channel, the server cancels the ongoing
-call and reinvokes the RPC with the new request. This applies to unary and
-streaming RPCs, though the server may not have an opportunity to cancel a
-synchronously handled unary RPC before it completes. The same RPC may be invoked
-multiple times simultaneously if the invocations are on different channels.
-
 Status codes
 ------------
 ``pw_rpc`` call objects (``ClientReaderWriter``, ``ServerReaderWriter``, etc.)