cmake: Add -W options to control deprecation warnings and errors

Refactor the -Wdev and -Wno-dev to use a generic -W parser that follows
the GCC pattern.  Include support for setting CMAKE_ERROR_DEPRECATED and
CMAKE_WARN_DEPRECATED via the deprecated warning.  Add -Werror=dev and
-Wno-error=dev options so that dev warning options are in line with
deprecated warning options.  Use a new CMAKE_SUPPRESS_DEVELOPER_ERRORS
internal cache entry to store the above new dev options persistently.
Add tests for new options and updated cmake documentation and release
notes to list new options.

1 files changed, 13 insertions, 0 deletions

diff --git a/Help/release/dev/cmake-W-options.rst b/Help/release/dev/cmake-W-options.rst
new file mode 100644
index 0000000..c0b51d0
--- /dev/null
+++ b/Help/release/dev/cmake-W-options.rst
@@ -0,0 +1,13 @@
+cmake-W-options
+---------------
+
+* The :variable:`CMAKE_ERROR_DEPRECATED` variable can now be set using the
+  ``-Werror=deprecated`` and ``-Wno-error=deprecated`` :manual:`cmake(1)`
+  options.
+
+* The :variable:`CMAKE_WARN_DEPRECATED` variable can now be set using the
+  ``-Wdeprecated`` and ``-Wno-deprecated`` :manual:`cmake(1)` options.
+
+* :manual:`cmake(1)` gained options ``-Werror=dev`` and ``-Wno-error=dev``
+  to control whether developer warnings intended for project authors
+  are treated as errors.