docs: add NetBSD instructions (#10)

README.md

@@ -35,6 +35,7 @@ flawz --feeds 2024 --query xz
   - [Cargo](#cargo)
   - [Arch Linux](#arch-linux)
   - [Alpine Linux](#alpine-linux)
+  - [NetBSD](#netbsd)
   - [Binary releases](#binary-releases)
   - [Build from source](#build-from-source)
 - [Usage](#usage)
@@ -88,6 +89,13 @@ pacman -S flawz
 apk add flawz
 ```
 
+### NetBSD
+**flawz** is available from the official repositories. To install it, simply run:
+
+```sh
+pkgin install flawz
+```
+
 ### Binary releases
 
 See the available binaries for different targets from the [releases page](https://github.com/orhun/flawz/releases).