docs: qbdefs.h: description must directly follow @file
docs: qbdefs.h: description must directly follow @file

If we want to see it again in the man page NAME section, where it can
be indexed by apropos or whatis.

kgaillot/libqb,ClusterLabs/libqb,kgaillot/libqb,ClusterLabs/libqb,ClusterLabs/libqb,kgaillot/libqb