Fix -ftrap-function fallout from llvm r145714.  <rdar://problem/10799325>

That llvm change removed the -trap-func backend option, so that using
-ftrap-function with clang would cause the backend to complain.  Fix it
by adding the trap function name to the CodeGenOptions and passing it through
to the TargetOptions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@149679 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/clang/Driver/CC1Options.td b/include/clang/Driver/CC1Options.td
index 3d36340..fd3e32c 100644
--- a/include/clang/Driver/CC1Options.td
+++ b/include/clang/Driver/CC1Options.td
@@ -154,6 +154,8 @@
   HelpText<"Place each function in its own section (ELF Only)">;
 def fdata_sections : Flag<"-fdata-sections">,
   HelpText<"Place each data in its own section (ELF Only)">;
+def ftrap_function_EQ : Joined<"-ftrap-function=">,
+  HelpText<"Issue call to specified function rather than a trap instruction">;
 def funroll_loops : Flag<"-funroll-loops">,
   HelpText<"Turn on loop unroller">;
 def femit_coverage_notes : Flag<"-femit-coverage-notes">,