sensor: Add new Accuracy interface

This will express the +/- percentage accuracy of the Value read. Default
to NaN (not a number).

Tested:
    Local CI build against phosphor-dbus-interfaces clean.
    Built p10bmc obmc-phosphor-image (devtool modify ...)
    Find and view client.hpp and server.hpp for Accuracy, looks good.

Change-Id: I42b93c0267cf6ce397c922a0c161c41a56c8b30e
Signed-off-by: Brandon Wyman <bjwyman@gmail.com>
diff --git a/gen/xyz/openbmc_project/Sensor/meson.build b/gen/xyz/openbmc_project/Sensor/meson.build
index 9e018b3..b4613c2 100644
--- a/gen/xyz/openbmc_project/Sensor/meson.build
+++ b/gen/xyz/openbmc_project/Sensor/meson.build
@@ -1,4 +1,18 @@
 # Generated file; do not modify.
+subdir('Accuracy')
+generated_others += custom_target(
+    'xyz/openbmc_project/Sensor/Accuracy__markdown'.underscorify(),
+    input: [ '../../../../yaml/xyz/openbmc_project/Sensor/Accuracy.interface.yaml',  ],
+    output: [ 'Accuracy.md' ],
+    command: [
+        sdbuspp_gen_meson_prog, '--command', 'markdown',
+        '--output', meson.current_build_dir(),
+        '--tool', sdbusplusplus_prog,
+        '--directory', meson.current_source_dir() / '../../../../yaml',
+        'xyz/openbmc_project/Sensor/Accuracy',
+    ],
+)
+
 subdir('Device')
 generated_others += custom_target(
     'xyz/openbmc_project/Sensor/Device__markdown'.underscorify(),