treewide: comply with the OpenBMC style guidelines

The guidelines say cpp source code filenames should be lower_snake_case:
https://github.com/openbmc/docs/blob/master/cpp-style-and-conventions.md#files

Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
Change-Id: Ia04017b0eb9a65ce1303af5b6dc36e730410fd91
diff --git a/src/meson.build b/src/meson.build
index 411f0d4..8ddb21e 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -3,12 +3,12 @@
 
 executable(
     'entity-manager',
-    'EntityManager.cpp',
-    'Expression.cpp',
-    'PerformScan.cpp',
-    'PerformProbe.cpp',
-    'Overlay.cpp',
-    'Utils.cpp',
+    'entity_manager.cpp',
+    'expression.cpp',
+    'perform_scan.cpp',
+    'perform_probe.cpp',
+    'overlay.cpp',
+    'utils.cpp',
     cpp_args: cpp_args + ['-DBOOST_ASIO_DISABLE_THREADS'],
     dependencies: [
         boost,
@@ -28,10 +28,10 @@
     endif
     executable(
         'fru-device',
-        'Expression.cpp',
-        'FruDevice.cpp',
-        'Utils.cpp',
-        'FruUtils.cpp',
+        'expression.cpp',
+        'fru_device.cpp',
+        'utils.cpp',
+        'fru_utils.cpp',
         cpp_args: cpp_args_fd,
         dependencies: [
             boost,