ARM64: use hex immediates for movz/movk instructions

Since these are mostly used in "lsl #16", "lsl #32", "lsl #48" combinations to
piece together an immediate in 16-bit chunks, hex is probably the most
appropriate format.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207635 91177308-0d34-0410-b5e6-96231b3b80d8
20 files changed