[bpf] add support for BPF backend

add support for bpfel/bpfeb targets

llvm-svn: 239496
diff --git a/clang/lib/Driver/ToolChains.cpp b/clang/lib/Driver/ToolChains.cpp
index 115a16f..02154dc 100644
--- a/clang/lib/Driver/ToolChains.cpp
+++ b/clang/lib/Driver/ToolChains.cpp
@@ -2084,6 +2084,8 @@
   case llvm::Triple::aarch64_be:
   case llvm::Triple::arm:
   case llvm::Triple::armeb:
+  case llvm::Triple::bpfel:
+  case llvm::Triple::bpfeb:
   case llvm::Triple::thumb:
   case llvm::Triple::thumbeb:
   case llvm::Triple::ppc: