dockerfile: Install the zip tool in the base image

This is needed when packaging the cross built toolchains anyway.

Dockerfile

@@ -3,7 +3,7 @@ FROM ubuntu:18.04
 RUN apt-get update -qq && apt-get install -qqy --no-install-recommends \
     git wget bzip2 file unzip libtool pkg-config cmake build-essential \
     automake yasm gettext autopoint vim-tiny python3 python3-distutils \
-    ninja-build ca-certificates curl less && \
+    ninja-build ca-certificates curl less zip && \
     apt-get clean -y && \
     rm -rf /var/lib/apt/lists/*
 

Dockerfile.cross

@@ -11,11 +11,6 @@
 ARG BASE=mstorsjo/llvm-mingw:dev
 FROM $BASE
 
-RUN apt-get update -qq && \
-    apt-get install -qqy zip && \
-    apt-get clean -y && \
-    rm -rf /var/lib/apt/lists/*
-
 ARG CROSS_ARCH=x86_64
 ENV CROSS_TOOLCHAIN_PREFIX=/opt/llvm-mingw-$CROSS_ARCH
 

Dockerfile.dev

@@ -3,7 +3,7 @@ FROM ubuntu:18.04
 RUN apt-get update -qq && apt-get install -qqy --no-install-recommends \
     git wget bzip2 file unzip libtool pkg-config cmake build-essential \
     automake yasm gettext autopoint vim-tiny python3 python3-distutils \
-    ninja-build ca-certificates curl less && \
+    ninja-build ca-certificates curl less zip && \
     apt-get clean -y && \
     rm -rf /var/lib/apt/lists/*