meson: remove cpp-fs dependency

Any compiler which supports C++17 doesn't have the std::filesystem
support in a separate library.  Remove all the meson magic to attempt to
find this because it is all integrated into the standard C++ library.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I1e788e38d26a825f2ee5836da740657ffb5ea072
diff --git a/test/meson.build b/test/meson.build
index 8db5caa..d06a326 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -37,6 +37,6 @@
                                     dump,
                                     phosphor_logging_dep,
                                     fmt_dep,
-                                    cppfs]),
+                                    ]),
        workdir: meson.current_source_dir())
 endforeach