Help: mark the directory properties INTERPROCEDURAL_OPTIMIZATION as deprecated

These properties actually never existed, so move the documentation
to "Deprecated" and refer to the target properties.

Help/manual/cmake-properties.7.rst

@@ -77,8 +77,6 @@ Properties on Directories
    /prop_dir/IMPORTED_TARGETS
    /prop_dir/INCLUDE_DIRECTORIES
    /prop_dir/INCLUDE_REGULAR_EXPRESSION
-   /prop_dir/INTERPROCEDURAL_OPTIMIZATION
-   /prop_dir/INTERPROCEDURAL_OPTIMIZATION_CONFIG
    /prop_dir/LABELS
    /prop_dir/LINK_DIRECTORIES
    /prop_dir/LINK_OPTIONS
@@ -621,6 +619,8 @@ Deprecated Properties on Directories
 
    /prop_dir/ADDITIONAL_MAKE_CLEAN_FILES
    /prop_dir/COMPILE_DEFINITIONS_CONFIG
+   /prop_dir/INTERPROCEDURAL_OPTIMIZATION
+   /prop_dir/INTERPROCEDURAL_OPTIMIZATION_CONFIG
    /prop_dir/TEST_INCLUDE_FILE
 
 

Help/prop_dir/INTERPROCEDURAL_OPTIMIZATION.rst

@@ -1,7 +1,6 @@
 INTERPROCEDURAL_OPTIMIZATION
 ----------------------------
 
-Enable interprocedural optimization for targets in a directory.
+This directory property does not exist anymore.
 
-If set to true, enables interprocedural optimizations if they are
-known to be supported by the compiler.
+See the target property :prop_tgt:`INTERPROCEDURAL_OPTIMIZATION` instead.

Help/prop_dir/INTERPROCEDURAL_OPTIMIZATION_CONFIG.rst

@@ -1,8 +1,6 @@
 INTERPROCEDURAL_OPTIMIZATION_<CONFIG>
 -------------------------------------
 
-Per-configuration interprocedural optimization for a directory.
+This directory property does not exist anymore.
 
-This is a per-configuration version of ``INTERPROCEDURAL_OPTIMIZATION``.
-If set, this property overrides the generic property for the named
-configuration.
+See the target property :prop_tgt:`INTERPROCEDURAL_OPTIMIZATION_<CONFIG>` instead.