Fix a little fallout from the changes in r174757 where we would
skip every other float/double/long double as we extracted data
from a buffer.
<rdar://problem/13485062>


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@177779 91177308-0d34-0410-b5e6-96231b3b80d8