Fix a weird ppc64-specific link error during an llvm-gcc build:

ld: bad offset (0x00000091) for lo14 instruction pic-base fix-up in ___popcountdi2 from libgcc/./_popcountsi2_s.o

The problem is that the non lazy symbol pointers need to be 8 byte aligned
on ppc64 and .section doesn't have an implicit alignment like ".non_lazy_symbol_pointer"
does.

llvm-svn: 78572