[PATCH] AArch64: use 32bit registers in ldr-pseudo.s tests

[David Peixotto]

It's not clear to me how this change improves the test. Rather than just renaming, I think it would be better to

1. Add tests for moving 32-bit constants to w registers
2. Add tests for moving 64-bit constants to x registers
3. Add tests for moving 64-bit constants to w registers (should produce an error).

http://reviews.llvm.org/D4278