Xcode: Inherit target library and framework search paths from project

Xcode has multiple levels of build settings with priority in descending
order:

1. Target
2. Project
3. Workspace
4. SDK defaults

`CMAKE_XCODE_ATTRIBUTE_*` path variables add these to project level, but
linked frameworks and libraries override this in target level.  Add the
`$(inherited)` macro to keep both in the final list.

Fixes: #21387