clang-tidy: Enable modernize-use-equals-default check

This check replaces default bodies of special member functions
with = default;.

The explicitly defaulted function declarations enable more
opportunities in optimization, because the compiler might treat
explicitly defaulted functions as trivial.

Signed-off-by: George Liu <liuxiwei@ieisystem.com>
Change-Id: I1860b4c1f416f892ae224f9fcd83170f1b63043a
diff --git a/.clang-tidy b/.clang-tidy
index e6cb2b4..873d901 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -217,6 +217,7 @@
 modernize-unary-static-assert,
 modernize-use-bool-literals,
 modernize-use-default-member-init,
+modernize-use-equals-default,
 modernize-use-equals-delete,
 modernize-use-noexcept,
 modernize-use-transparent-functors,