ppc476 sections that end exactly on a page boundary need the
workaround applied when a function ends in "bctr", or when pasting
together code from multiple sections. The space allocated for the
patch area didn't allow for this case, while the code in
relocate_section performing the patches did, leading to an assertion
failure.
* elf32-ppc.c (ppc_elf_relax_section): Fix off by one error.