gperftools: remove gperftools-headers package

gperftools: remove gperftools-headers package

The gperftools-headers package installed headers to the target device,
but headers are only needed during the build process (via Build/InstallDev).

- Remove gperftools-headers package
- Rename gperftools-runtime to gperftools
- Add ABI_VERSION for tracking ABI changes

While looking for e.g. on repology, there is only gperftools package [1]
and not gperftools-runtime and gperftools-headers.

[1] https://repology.org/project/gperftools/versions

Signed-off-by: Josef Schlehofer <[email protected]>