[CMake] Fix generated config install location

The expected install locations for the SwiftCoreConfig.cmake and
SwiftCoreTargets.cmake file was inconsistent between the build directory
and the install location. Making everything consistent across install
locations. In both cases, the files are installed under
`./cmake/SwiftCore`. This is one of the formats that `find_package` uses
to automatically search for package config files so that we can avoid
passing `SwiftCore_DIR` to all sub-projects.

Author: etcwilde

Runtimes/Core/CMakeLists.txt

@@ -225,12 +225,12 @@ install(EXPORT SwiftCoreTargets
   COMPONENT SwiftCore_cmake)
 include(CMakePackageConfigHelpers)
 configure_package_config_file("${CMAKE_CURRENT_SOURCE_DIR}/cmake/interface/SwiftCoreConfig.cmake.in"
-  "${CMAKE_CURRENT_BINARY_DIR}/cmake/SwiftCoreConfig.cmake"
+  "${CMAKE_CURRENT_BINARY_DIR}/cmake/SwiftCore/SwiftCoreConfig.cmake"
   INSTALL_DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/SwiftCore")
-write_basic_package_version_file("${CMAKE_CURRENT_BINARY_DIR}/cmake/SwiftCoreConfigVersion.cmake"
+write_basic_package_version_file("${CMAKE_CURRENT_BINARY_DIR}/cmake/SwiftCore/SwiftCoreConfigVersion.cmake"
   VERSION "${PROJECT_VERSION}"
   COMPATIBILITY ExactVersion)
 install(FILES
-  "${CMAKE_CURRENT_BINARY_DIR}/cmake/SwiftCoreConfig.cmake"
-  "${CMAKE_CURRENT_BINARY_DIR}/cmake/SwiftCoreConfigVersion.cmake"
+  "${CMAKE_CURRENT_BINARY_DIR}/cmake/SwiftCore/SwiftCoreConfig.cmake"
+  "${CMAKE_CURRENT_BINARY_DIR}/cmake/SwiftCore/SwiftCoreConfigVersion.cmake"
   DESTINATION "${CMAKE_INSTALL_LIBDIR}/cmake/SwiftCore")

Runtimes/Core/cmake/interface/SwiftCoreConfig.cmake.in

@@ -1,5 +1,5 @@
 @PACKAGE_INIT@
-include("${CMAKE_CURRENT_LIST_DIR}/SwiftCore/SwiftCoreTargets.cmake")
+include("${CMAKE_CURRENT_LIST_DIR}/SwiftCoreTargets.cmake")
 
 set(SwiftCore_ENABLE_LIBRARY_EVOLUTION @SwiftCore_ENABLE_LIBRARY_EVOLUTION@)