Added a new argument to add_swift_target_library to control the install_name_dir.

(cherry picked from commit bec25a1)

Author: Ross Bayer

cmake/modules/AddSwift.cmake

@@ -713,6 +713,7 @@ function(_add_swift_library_single target name)
         DEPLOYMENT_VERSION_TVOS
         DEPLOYMENT_VERSION_WATCHOS
         INSTALL_IN_COMPONENT
+        LIBRARY_INSTALL_NAME_DIR
         MODULE_TARGET
         SDK)
   set(SWIFTLIB_SINGLE_multiple_parameter_options
@@ -1033,6 +1034,10 @@ function(_add_swift_library_single target name)
       set(install_name_dir "@rpath")
     endif()
 
+    if(SWIFTLIB_SINGLE_LIBRARY_INSTALL_NAME_DIR)
+      set(install_name_dir "${SWIFTLIB_SINGLE_LIBRARY_INSTALL_NAME_DIR}")
+    endif()
+
     set_target_properties("${target}"
       PROPERTIES
       INSTALL_NAME_DIR "${install_name_dir}")
@@ -1613,7 +1618,8 @@ function(add_swift_target_library name)
         DEPLOYMENT_VERSION_OSX
         DEPLOYMENT_VERSION_TVOS
         DEPLOYMENT_VERSION_WATCHOS
-        INSTALL_IN_COMPONENT)
+        INSTALL_IN_COMPONENT
+        LIBRARY_INSTALL_NAME_DIR)
   set(SWIFTLIB_multiple_parameter_options
         C_COMPILE_FLAGS
         DEPENDS
@@ -1911,6 +1917,7 @@ function(add_swift_target_library name)
         ${SWIFTLIB_TARGET_LIBRARY_keyword}
         ${SWIFTLIB_FORCE_BUILD_OPTIMIZED_keyword}
         ${SWIFTLIB_NOSWIFTRT_keyword}
+        LIBRARY_INSTALL_NAME_DIR "${SWIFTLIB_LIBRARY_INSTALL_NAME_DIR}"
         INSTALL_IN_COMPONENT "${SWIFTLIB_INSTALL_IN_COMPONENT}"
         DEPLOYMENT_VERSION_OSX "${SWIFTLIB_DEPLOYMENT_VERSION_OSX}"
         DEPLOYMENT_VERSION_IOS "${SWIFTLIB_DEPLOYMENT_VERSION_IOS}"