Fix incorrect encoding of single and double precision registers for some VFP instructions. Also fix incorrect disassembling of vldr/vstr.  This is a commit of http://codereview.chromium.org/3107027 for Rodolph Perfetta.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5352 ce2b1a6d-e550-0410-aec6-3dcde31c8c00