fixes comments

Author: ringabout

lib/system/channels_builtin.nim

@@ -369,14 +369,14 @@ proc sendImpl(q: PRawChannel, typ: PNimType, msg: pointer, noBlock: bool): bool
 
 when defined(gcDestructors):
   proc send*[TMsg](c: var Channel[TMsg], msg: sink TMsg) {.inline.} =
-    ## Sends a message to a thread. `msg` is deeply copied.
+    ## Sends a message to a thread.
     discard sendImpl(cast[PRawChannel](addr c), cast[PNimType](getTypeInfo(msg)), unsafeAddr(msg), false)
     wasMoved(msg)
 
   proc trySend*[TMsg](c: var Channel[TMsg], msg: sink TMsg): bool {.inline.} =
     ## Tries to send a message to a thread.
     ##
-    ## `msg` is deeply copied. Doesn't block.
+    ## Doesn't block.
     ##
     ## Returns `false` if the message was not sent because number of pending items
     ## in the channel exceeded `maxItems`.