Add support for riscv

This is initial support for being able to build against a riscv64
architecture target.

xref: coreos/fedora-coreos-tracker#1931

Author: dustymabe

build.sh

@@ -30,6 +30,7 @@ set -x
 srcdir=$(pwd)
 
 configure_yum_repos() {
+    [ "${arch}" == "riscv64" ] && return # No continuous repo for riscv64 yet
     local version_id
     version_id=$(. /etc/os-release && echo ${VERSION_ID})
     # Add continuous tag for latest build tools and mark as required so we
@@ -102,6 +103,7 @@ install_rpms() {
 # and it is very useful to have in the same place/flow as where we do builds/tests related
 # to CoreOS.
 install_ocp_tools() {
+    [ "${arch}" == "riscv64" ] && return # No ocp tools for riscv64
     # If $OCP_VERSION is defined we'll grab that specific version.
     # Otherwise we'll get the latest.
     local url="https://mirror.openshift.com/pub/openshift-v4/${arch}/clients/ocp/latest${OCP_VERSION:+-$OCP_VERSION}/openshift-client-linux.tar.gz"

mantle/build

@@ -10,7 +10,7 @@ if [[ $# -eq 0 ]]; then
     set -- cmd/* schema
 fi
 
-declare -A BASEARCH_TO_GOARCH=([s390x]=s390x [x86_64]=amd64 [aarch64]=arm64 [ppc64le]=ppc64le)
+declare -A BASEARCH_TO_GOARCH=([x86_64]=amd64 [aarch64]=arm64 [ppc64le]=ppc64le [riscv64]=riscv64 [s390x]=s390x)
 ARCH=$(arch)
 KOLET_ARCHES="${KOLET_ARCHES:-$(ARCH)}"
 

src/cmd-osbuild

@@ -337,7 +337,7 @@ main() {
     fi
 
     case "$basearch" in
-        "x86_64"|"aarch64"|"s390x"|"ppc64le") ;;
+        "x86_64"|"aarch64"|"s390x"|"ppc64le"|"riscv64") ;;
         *) fatal "$basearch is not supported for this command" ;;
     esac