Bring in APR-util's DLL_NAME feature, used to provide a specific name
for DSO modules as the Window's File Description.  This was lost with
the merge of APR-util into APR.

Set DLL_NAME in the cmake-based build.  (The Visual Studio build already
sets it.)

The APR-util 1.5.x cmake list already sets it.


git-svn-id: https://svn.apache.org/repos/asf/apr/apr/trunk@1523277 13f79535-47bb-0310-9956-ffa450edef68