[X86][SSE] Ensure float load/stores use the WriteFLoad/WriteFStore scheduler classes

Retag some instructions that were missed when we split off vector load/store/moves - MOVSS/MOVSD/MOVHPD/MOVHPD/MOVLPD/MOVLPS etc.

Fixes BtVer2/SLM which have different behaviours for GPR stores.

llvm-svn: 332714