[ELF] - Another fix for "LLD crashes with --emit-relocs when trying to proccess .eh_frame"

This fixes PR36367 which is about segfault when --emit-relocs is
used together with .eh_frame sections which happens because
of reordering of regular and .rel[a] sections.

Path changes loop that iterates over input sections to create
relocation target sections first.

Differential revision: https://reviews.llvm.org/D44679

llvm-svn: 328299