Send unmaintained hardened_malloc-rs to valhalla.

Signed-off-by: Jason Volk <jason@zemos.net>

src/main/Cargo.toml

@@ -100,9 +100,6 @@ gzip_compression = [
 	"tuwunel-router/gzip_compression",
 	"tuwunel-service/gzip_compression",
 ]
-hardened_malloc = [
-	"tuwunel-core/hardened_malloc",
-]
 io_uring = [
 	"tuwunel-admin/io_uring",
 	"tuwunel-api/io_uring",
@@ -236,10 +233,6 @@ tracing-opentelemetry.workspace = true
 tracing-subscriber.workspace = true
 tracing.workspace = true
 
-[target.'cfg(all(not(target_env = "msvc"), target_os = "linux"))'.dependencies]
-hardened_malloc-rs.workspace = true
-hardened_malloc-rs.optional = true
-
 [lints]
 workspace = true