On AArch64 the pseudo instruction ldr <reg>, =... supports both
32-bit and 64-bit constants. Add support for 64 bit constants for
the pools to support the pseudo instruction fully.
Changes the AArch64 ldr-pseudo tests to use 32-bit registers and
adds tests with 64-bit registers.
Patch by Janne Grunau!
Differential Revision: http://reviews.llvm.org/D4279
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213387 91177308-0d34-0410-b5e6-96231b3b80d8
