client: Make Put always return the dir entry put.
client: Make Put always return the dir entry put.

Change-Id: I5c6d8b2b9ac30f2705eaf1c1bf7cc8303a45140c
Reviewed-on: https://upspin-review.googlesource.com/4960
Reviewed-by: Rob Pike <4dc7c9ec434ed06502767136789763ec11d2c4b7@google.com>
Reviewed-by: Andrew Gerrand <395a7d33bec8475c9b83b7d440f141bcbd994aa5@google.com>

upspin/upspin,upspin/upspin