tests/kernel: Disable -Werror when testing deprecated pipe APIs

These two tests are validating that deprecated APIs still work
correctly. Which means they will definitely generate compile warnings.

To disable -Werror while letting it be enabled for other tests, create a
new Kconfig variable, DEPRECATION_TEST and make
COMPILER_WARNINGS_AS_ERRORS depend on that option being unselected. Add
this option to the two tests so that the resulting configuration
disables -Werror.

Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>

Author: keith-packard

Kconfig.zephyr

@@ -542,9 +542,18 @@ config LTO
 
 config COMPILER_WARNINGS_AS_ERRORS
 	bool "Treat warnings as errors"
+	depends on !DEPRECATION_TEST
 	help
 	  Turn on "warning as error" toolchain flags
 
+config DEPRECATION_TEST
+	bool "Indicate test for deprecated feature"
+	help
+	  This option is selected by tests which check functionality of
+	  deprecated features. It ensures that COMPILER_WARNINGS_AS_ERRORS
+	  is not selected as that would generate errors when the deprecated
+	  features are used.
+
 config COMPILER_SAVE_TEMPS
 	bool "Save temporary object files"
 	help

tests/kernel/pipe/deprecated/pipe/prj.conf

@@ -3,3 +3,4 @@ CONFIG_TEST_USERSPACE=y
 CONFIG_MP_MAX_NUM_CPUS=1
 CONFIG_TIMESLICE_SIZE=0
 CONFIG_PIPES=y
+CONFIG_DEPRECATION_TEST=y

tests/kernel/pipe/deprecated/pipe_api/prj.conf

@@ -5,3 +5,4 @@ CONFIG_DYNAMIC_OBJECTS=y
 CONFIG_MP_MAX_NUM_CPUS=1
 CONFIG_ZTEST_FATAL_HOOK=y
 CONFIG_PIPES=y
+CONFIG_DEPRECATION_TEST=y