regulators: Create exception_utils namespace

This namespace contains utility functions for handling exceptions.

Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
Change-Id: Ie945c7882cdede398af56dcd2d2c3c9c70320e92
diff --git a/phosphor-regulators/test/meson.build b/phosphor-regulators/test/meson.build
index d23bdf1..242c02a 100644
--- a/phosphor-regulators/test/meson.build
+++ b/phosphor-regulators/test/meson.build
@@ -9,6 +9,7 @@
     'config_file_parser_tests.cpp',
     'configuration_tests.cpp',
     'device_tests.cpp',
+    'exception_utils_tests.cpp',
     'id_map_tests.cpp',
     'mock_journal.cpp',
     'pmbus_error_tests.cpp',