[cmake] Add missing dependency between component and its targets (#76596)
`swift_install_in_component` does not create a dependency between its
`TARGETS` and the `COMPONENT`, so one has to be created manually.
The missing dependency might cause invocations to CMake/Ninja for the
`install-*` targets to not build the required files before the
installation is performed. Because the normal `build-script` builds the
`all` target, this kind of missing dependencies like this are common.
This bit of code appeared in #76497 some days ago.