Simplify copying over operands from pseudo NEON load/store instructions.

Simplify copying over operands from pseudo NEON load/store instructions.
For VLD3/VLD4 with double-spaced registers, add the implicit use of the
super register for both the instruction loading the even registers and the
instruction loading the odd registers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113452 91177308-0d34-0410-b5e6-96231b3b80d8