Update README.md to mention what packages are needed in FreeBSD

Author: su8

README.md

@@ -44,7 +44,9 @@ static void hide_show(const Arg *arg) {
 ```
 
 The packages needed for example would be
-`libxcb` `xcb-util` `xcb-util-wm` `xcb-util-keysym` `gcc` `make` `xorg` 
+`libxcb` `xcb-util` `xcb-util-wm` `xcb-util-keysym` `gcc` `make` `xorg` [ `pkg-config` or `pkgconfig`or `pkgconf` ]
+
+For FreeBSD the packages are `gcc` `xorg` `gmake` `chromium` `git` `gawk` `libxcb` `xcb-util` `xcb-util-wm` `xcb-util-keysyms` `pkgconf`
 
 Bugs
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