platform-mc: Create Numeric sensor D-Bus object

Added numeric_sensor class. The NumericSensor class will create the
Numeric sensor D-Bus object. The class also handles sensor status and
exports its status to D-Bus interfaces.

tested: Verified on ast2600 EVB which is connected to a PLDM device
over I2C. bmcweb can display the state of numeric sensor.

Signed-off-by: Thu Nguyen <thu@os.amperecomputing.com>
Change-Id: I1c7de2e74100ed787ed2119896d3c5b36098dd96
diff --git a/meson.build b/meson.build
index bfbf63e..af6bf6e 100644
--- a/meson.build
+++ b/meson.build
@@ -72,6 +72,7 @@
 elif get_option('transport-implementation') == 'af-mctp'
   conf_data.set('PLDM_TRANSPORT_WITH_AF_MCTP', 1)
 endif
+conf_data.set('DEFAULT_SENSOR_UPDATER_INTERVAL', get_option('default-sensor-update-interval'))
 
 configure_file(output: 'config.h',
   configuration: conf_data
@@ -174,6 +175,7 @@
   'platform-mc/terminus.cpp',
   'platform-mc/platform_manager.cpp',
   'platform-mc/manager.cpp',
+  'platform-mc/numeric_sensor.cpp',
   'requester/mctp_endpoint_discovery.cpp',
   implicit_include_directories: false,
   dependencies: deps,