Update MXE dependencies

advanced/cross-compile-silent-dragon-for-windows-with-mxe.md

@@ -33,6 +33,7 @@ sudo apt-get install \
     libc6-dev-i386 \
     libgdk-pixbuf2.0-dev \
     libltdl-dev \
+    libgl-dev \
     libssl-dev \
     libtool-bin \
     libxml-parser-perl \
@@ -42,7 +43,9 @@ sudo apt-get install \
     p7zip-full \
     patch \
     perl \
-    python \
+    python3 \
+    python3-mako \
+    python3-pkg-resources \
     ruby \
     sed \
     unzip \