Adding support for deregistering EH frames with MCJIT.

Patch by Yaron Keren



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192753 91177308-0d34-0410-b5e6-96231b3b80d8
Adding padding to the .eh_frame section in RuntimeDyld

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192754 91177308-0d34-0410-b5e6-96231b3b80d8
Simplify zero initialization of DIEAttrs variable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192755 91177308-0d34-0410-b5e6-96231b3b80d8