[VE] notify and build as official target

[simoll]

Summary

VE is an official target, adapt the clang-ve-ninja builder accordingly.

Depends on D113247 - the official backend status.

[gkistanova]

LGTM.

[simoll]

Add change to build clang-ve-ninja on the hpce-ve-main worker, which is to be connected to the main buildmaster.

[simoll]

NFC. Rebased onto commit that added the hpce-ve-main and hpce-ve-staging workers.

buildbot/osuosl/master/config/status.py

reporters.MailNotifier(
         sendToInterestedUsers = False,
         extraRecipients = ["[e-mail]"],
         subject = "Build %(builder)s Failure",
         mode = "failing",
         builders = ["llvm-riscv-linux"]),
     reporters.MailNotifier(
         fromaddr = "[e-mail]",
         sendToInterestedUsers = False,
+        extraRecipients = ["[e-mail]"],
+        subject = "Build %(builder)s Failure",
+        mode = "failing",
+        builders = ["clang-ve-ninja"]),
+    reporters.MailNotifier(
+        fromaddr = "[e-mail]",
+        sendToInterestedUsers = False,
         extraRecipients = ["[e-mail]",
                            "[e-mail]",
                            "[e-mail]"],
         subject = "Build %(builder)s Failure",
         mode = "failing",
         builders = ["lldb-x64-windows-ninja"]),
     reporters.MailNotifier(
         fromaddr = "[e-mail]",

zorg/buildbot/builders/annotated/ve-linux-steps.make

build-llvm:
   touch ${TOOL_CONFIG_CACHE}
   mkdir -p ${LLVM_BUILD}
   cd ${LLVM_BUILD} && ${CMAKE} ${MONOREPO}/llvm -G Ninja \
         -C ${TOOL_CONFIG_CACHE} \
         -DCMAKE_BUILD_TYPE=RelWithDebInfo \
         -DLLVM_BUILD_LLVM_DYLIB=Off \
         -DLLVM_LINK_LLVM_DYLIB=Off \
         -DCLANG_LINK_CLANG_DYLIB=Off \
-        -DLLVM_TARGETS_TO_BUILD="X86" \
-        -DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD="VE" \
+        -DLLVM_TARGETS_TO_BUILD="X86;VE" \
         -DLLVM_ENABLE_PROJECTS="clang" \
         -DCMAKE_INSTALL_PREFIX="${LLVM_PREFIX}" \
         -DLLVM_INSTALL_UTILS=On
   cd ${LLVM_BUILD} && ${NINJA}
 
 # install-llvm:
 #   # build-llvm
 #   cd ${LLVM_BUILD} && ${NINJA} install