README.md: Update installation command on Arch Linux
@@ -22,7 +22,7 @@ On __Fedora 20 and above__, type:
`yum install SDL2{,_mixer,_image,_ttf}-devel`
On __Arch Linux__, type:
-`pacman -S sdl2{,_mixer,_image,_ttf}`
+`pacman -S sdl2{,_mixer,_image,_ttf,_gfx}`
On __Gentoo__, type:
`emerge -av libsdl2 sdl2-{gfx,image,mixer,ttf}`
