Jenkins: Boot the dev branch of CheriBSD for RISC-V

The main branch of CheriBSD has test failures with tag-clearing QEMU as
it expects trapping behaviour and those changes will not be cherry-picked,
so we have to boot dev until main is updated.

Jenkinsfile

@@ -83,7 +83,10 @@ def bootCheriBSD(params, String qemuConfig, String stageSuffix, String archSuffi
  def compressedDiskImage = "artifacts-${archSuffix}/cheribsd-${archSuffix}.img.xz"
  dir (stageSuffix) {
  sh "rm -rfv artifacts-${archSuffix}/cheribsd-*.img* artifacts-${archSuffix}/kernel*"
- copyArtifacts projectName: "CheriBSD-pipeline/main", filter: "${compressedDiskImage}, ${compressedKernel}",
+ // The main branch of CheriBSD has test failures with tag-clearing QEMU, so use dev for now.
+ // FIXME: boot CheriBSD-pipeline/main once there are no breaking changes to CHERI-RISC-V.
+ def cheribsdBranch = archSuffix.contains("riscv") ? "dev" : "main";
+ copyArtifacts projectName: "CheriBSD-pipeline/${cheribsdBranch}", filter: "${compressedDiskImage}, ${compressedKernel}",
  target: '.', fingerprintArtifacts: false, flatten: false, selector: lastSuccessful()
  }
  def testExtraArgs = [