Rename pkgconfig file to KF6Baloo
Helps with co-installability with KF5 and is also consistent with the other Frameworks and the CMake config files. While at it, also use ecm_generate_pkgconfig_file instead of configure_file.
Helps with co-installability with KF5 and is also consistent with the other Frameworks and the CMake config files. While at it, also use ecm_generate_pkgconfig_file instead of configure_file.