[PowerPC] fix register alignment for long double type

This patch fixes register alignment for long double type in
soft float mode. Before this patch alignment was 8 and this
patch changes it to 4.
Differential Revision: http://reviews.llvm.org/D18034



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268909 91177308-0d34-0410-b5e6-96231b3b80d8
7 files changed