The current mongo-c-driver/build/rpm/mongo-c-driver.spec fails to build on either Centos 6.7 or Centos 7.2. There are mistakes in the %changelog information and the documentation (manuals) are not fully specified, hence rpmbuild fails.
I have attached a spec file I have tested on centos 6.7 and 7.2 on CDRIVER versions 1.3.3, 1.3.4 and 1.3.5.
The spec file also documents how to build the rpms.
I hope you consider this update for inclusion in the driver.
I apologize if I have not submitted this patch correctly, but git is totally new for me.
I have only tested back to 1.3.3.