build: Move yaml files into a subdirectory

This improves generation speed and ensures that the yamldir only
contains yaml files.

Change-Id: I6094f23dfc4af2bb43ca7fdba047014142e1991f
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/gen/xyz/openbmc_project/Network/Neighbor/CreateStatic/meson.build b/gen/xyz/openbmc_project/Network/Neighbor/CreateStatic/meson.build
index 5144d7b..7bc95ee 100644
--- a/gen/xyz/openbmc_project/Network/Neighbor/CreateStatic/meson.build
+++ b/gen/xyz/openbmc_project/Network/Neighbor/CreateStatic/meson.build
@@ -1,13 +1,13 @@
 # Generated file; do not modify.
 generated_sources += custom_target(
     'xyz/openbmc_project/Network/Neighbor/CreateStatic__cpp'.underscorify(),
-    input: [ '../../../../../../xyz/openbmc_project/Network/Neighbor/CreateStatic.interface.yaml',  ],
+    input: [ '../../../../../../yaml/xyz/openbmc_project/Network/Neighbor/CreateStatic.interface.yaml',  ],
     output: [ 'server.cpp', 'server.hpp', 'client.hpp',  ],
     command: [
         sdbuspp_gen_meson_prog, '--command', 'cpp',
         '--output', meson.current_build_dir(),
         '--tool', sdbusplusplus_prog,
-        '--directory', meson.current_source_dir() / '../../../../../..',
+        '--directory', meson.current_source_dir() / '../../../../../../yaml',
         'xyz/openbmc_project/Network/Neighbor/CreateStatic',
     ],
 )