protobuf-c: update to 1.4.1.

protobuf-c (1.4.1)

  [ Robert Edmonds ]
  * Release 1.4.1

  [ Todd C. Miller ]
  * Only shift unsigned values to avoid implementation-specific behavior
    (#506, #508).
  * Fix regression with zero-length messages introduced in protobuf-c PR 500.
  * Fix a clang analyzer 14 warning about a possible NULL deref (#512, #514).

  [ steed717 ]
  * Fix unsigned integer overflow (#499, #513).

(wiz)