fileapi: Fix codemodel target install destination for cross-dir rules
Since commit e89ad0f94e (install: Allow installing targets created in
another directory, 2018-06-18, v3.13.0-rc1~407^2) we support calling
`install(TARGETS)` for targets created in another directory. However,
install generators are associated with the directory in which the call
to `install()` appears. This may not be the same directory in which the
target is defined. Record in each target the list of install generators
it has.
Fixes: #19546
6 files changed
