Add support for code generation of the one register with immediate form of vorr.

Add support for code generation of the one register with immediate form of vorr.
We could be more aggressive about making this work for a larger range of constants,
but this seems like a good start.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118201 91177308-0d34-0410-b5e6-96231b3b80d8