linux_riscv: Add 4.16-rc1.

Fixes #35148.

pkgs/os-specific/linux/kernel/patches.nix

@@ -72,4 +72,20 @@ rec {
       sha256 = "09096npxpgvlwdz3pb3m9brvxh7vy0xc9z9p8hh85xyczyzcsjhr";
     };
   };
+
+  riscv_modules = {
+    name = "riscv-modules";
+    patch = ./riscv-modules.patch;
+  };
+
+  riscv_irq_busy = {
+    name = "riscv-irq-busy";
+    patch = ./riscv-irq-busy.patch;
+  };
+
+  riscv_install = {
+    name = "riscv-install";
+    patch = ./riscv-install.patch;
+  };
+
 }