Doc: Add mention of webp

Author: Fuzzbawls

doc/build-unix.md

@@ -110,7 +110,7 @@ To build without GUI pass `--without-gui`.
 
 To build with Qt 5 you need the following:
 
-    sudo apt-get install libqt5gui5 libqt5core5a libqt5dbus5 libqt5svg5-dev libqt5charts5-dev qttools5-dev qttools5-dev-tools libqrencode-dev
+    sudo apt-get install libqt5gui5 libqt5core5a libqt5dbus5 libqt5svg5-dev libqt5charts5-dev qttools5-dev qttools5-dev-tools qt5-image-formats-plugins libqrencode-dev
 
 **Note:** Ubuntu versions prior to Bionic (18.04), and Debian version prior to Buster, do not have the `libqt5charts5-dev` package. If you are compiling on one of these older versions, you will need to omit `libqt5charts5-dev` from the above command.
 

doc/dependencies.md

@@ -17,6 +17,7 @@ These are the dependencies currently used by PIVX Core. You can find instruction
 | libnatpmp | [20150609](https://miniupnp.tuxfamily.org/files) |  | No |  |  |
 | libjpeg |  |  |  |  | [Yes](https://github.com/pivx-project/pivx/blob/master/depends/packages/qt.mk#L65) |
 | libpng |  |  |  |  | [Yes](https://github.com/pivx-project/pivx/blob/master/depends/packages/qt.mk#L64) |
+| libwebp | | | | | [Yes](https://github.com/pivx-project/pivx/blob/master/depends/packages/qt.mk#L22) |
 | librsvg | |  |  |  |  |
 | MiniUPnPc | [2.2.2](https://miniupnp.tuxfamily.org/files) |  | No |  |  |
 | GMP | [6.1.2](https://gmplib.org/) | | No | | |