This adds support for the .short and its alias .hword for adding literal values
into the object file. This is similar to the .word directive, however, rather
than inserting a value of 4 bytes, adds a 2-byte value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@201968 91177308-0d34-0410-b5e6-96231b3b80d8