Fix clang-tidy performance warnings in syste/core.

* Use const reference type for parameters to avoid unnecessary copy.
* Suppress warning of not using faster overloaded string find function.

Bug: 30407689
Bug: 30411878
Change-Id: I6cfdbbd50cf5e8f3db6e5263076d3a17a9a791ee
Test: build with WITH_TIDY=1
Merged-In: Ie79dbe21899867bc62031f8618bb1322b8071525
diff --git a/init/util.h b/init/util.h
index 9d522cc..f020da8 100644
--- a/init/util.h
+++ b/init/util.h
@@ -55,7 +55,7 @@
 void remove_link(const char *oldpath, const char *newpath);
 int wait_for_file(const char *filename, int timeout);
 void import_kernel_cmdline(bool in_qemu,
-                           std::function<void(const std::string&, const std::string&, bool)>);
+                           const std::function<void(const std::string&, const std::string&, bool)>&);
 int make_dir(const char *path, mode_t mode);
 int restorecon(const char *pathname);
 int restorecon_recursive(const char *pathname);