chore: add vendor dependencies for kauma build

vendor/memchr/src/macros.rs

@@ -0,0 +1,20 @@
+// Some feature combinations result in some of these macros never being used.
+// Which is fine. Just squash the warnings.
+#![allow(unused_macros)]
+
+macro_rules! log {
+    ($($tt:tt)*) => {
+        #[cfg(feature = "logging")]
+        {
+            $($tt)*
+        }
+    }
+}
+
+macro_rules! debug {
+    ($($tt:tt)*) => { log!(log::debug!($($tt)*)) }
+}
+
+macro_rules! trace {
+    ($($tt:tt)*) => { log!(log::trace!($($tt)*)) }
+}