avoid a few zeroMem (#932)

libp2p/stream/lpstream.nim

@@ -276,7 +276,7 @@ proc readLp*(s: LPStream, maxSize: int): Future[seq[byte]] {.async, gcsafe, publ
   if length == 0:
     return
 
-  var res = newSeq[byte](length)
+  var res = newSeqUninitialized[byte](length)
   await s.readExactly(addr res[0], res.len)
   return res
 

libp2p/vbuffer.nim

@@ -43,7 +43,7 @@ proc initVBuffer*(data: seq[byte], offset = 0): VBuffer =
 
 proc initVBuffer*(data: openArray[byte], offset = 0): VBuffer =
   ## Initialize VBuffer with copy of ``data``.
-  result.buffer = newSeq[byte](len(data))
+  result.buffer = newSeqUninitialized[byte](len(data))
   if len(data) > 0:
     copyMem(addr result.buffer[0], unsafeAddr data[0], len(data))
   result.offset = offset