regulators: Implement i2c_write_bytes action

Implement the i2c_write_bytes action in the JSON config file.  See
i2c_write_bytes.md for more information about this action.

Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
Change-Id: Ifd4ef481f0a6b74bd3e5689a7b9f3a989ed5e214
diff --git a/phosphor-regulators/test/meson.build b/phosphor-regulators/test/meson.build
index f6a351c..0dc4c56 100644
--- a/phosphor-regulators/test/meson.build
+++ b/phosphor-regulators/test/meson.build
@@ -18,6 +18,7 @@
     'actions/i2c_compare_byte_action_tests.cpp',
     'actions/i2c_compare_bytes_action_tests.cpp',
     'actions/i2c_write_byte_action_tests.cpp',
+    'actions/i2c_write_bytes_action_tests.cpp',
     'actions/if_action_tests.cpp',
     'actions/not_action_tests.cpp',
     'actions/or_action_tests.cpp',