automation: Add container for riscv64 builds

Add a container for cross-compiling xen to riscv64.
This just includes the cross-compiler and necessary packages for
building xen itself (packages for tools, stubdoms, etc., can be
added later).

Signed-off-by: Connor Davis <connojdavis@gmail.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

automation/build/archlinux/riscv64.dockerfile

@@ -0,0 +1,19 @@
+FROM archlinux
+LABEL maintainer.name="The Xen Project" \
+      maintainer.email="xen-devel@lists.xenproject.org"
+
+# Packages needed for the build
+RUN pacman --noconfirm --needed -Syu \
+    base-devel \
+    git \
+    inetutils \
+    riscv64-linux-gnu-binutils \
+    riscv64-linux-gnu-gcc \
+    riscv64-linux-gnu-glibc
+
+# Add compiler path
+ENV CROSS_COMPILE=riscv64-linux-gnu-
+
+RUN useradd --create-home user
+USER user
+WORKDIR /build

automation/scripts/containerize

@@ -26,6 +26,7 @@ BASE="registry.gitlab.com/xen-project/xen"
 case "_${CONTAINER}" in
     _alpine) CONTAINER="${BASE}/alpine:3.12" ;;
     _archlinux|_arch) CONTAINER="${BASE}/archlinux:current" ;;
+    _riscv64) CONTAINER="${BASE}/archlinux:riscv64" ;;
     _centos7) CONTAINER="${BASE}/centos:7" ;;
     _centos72) CONTAINER="${BASE}/centos:7.2" ;;
     _fedora) CONTAINER="${BASE}/fedora:29";;