README.md: drop qt5-default, add libsdl2-dev libbpf-dev llvm clang

qt5-default is obsolete, but add other libraries to allow a full
build of v4l-utils.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

README.md

@@ -28,8 +28,8 @@ packages with `apt-get` or `aptitude`:
 
 ```
 debhelper doxygen gcc git graphviz libasound2-dev libjpeg-dev
-libqt5opengl5-dev libudev-dev libx11-dev meson pkg-config qt5-default
-qtbase5-dev udev
+libqt5opengl5-dev libudev-dev libx11-dev meson pkg-config
+qtbase5-dev udev libsdl2-dev libbpf-dev llvm clang
 ```
 
 On Fedora, the package list for a minimal install with `dnf` or `yum` is: