cups-kyocera (cups driver): use patchPpdFilesHook
The `sed` script in the `installPhase` is removed.
Instead, the setup hook `patchPpdFilesHook`
is used to patch the path to `rastertokpsl`.
The result should essentially be the same.
Comparing the generated ppd files showed no difference
(short of the package's hash in the absolute paths).
The new package also contains a `propagated-build-inputs`
file which propagates the package itself.
This ensures the package is available whenever
a ppd file is singled out by another package.