Quieten warning about uninitialized use of d pointer

We had this issue in Qt 4 before: Clang considers the use of d uninitialized
in the initializer list for d. This might or might not be legal, the clang
devs are divided on that topic. Let's just use a more common form and ignore
the issue language lawyers.

Change-Id: I3324255963a6d0f4a9057fe0d1d9ae868d3efef7
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>