PR ld/975: [Regression]: ld -pie generates DT_TEXTREL

[H. J. Lu]

This is caused by not defining array bonds in elf.sc. The problem
is when bfd_elf_size_dynamic_sections is called by
gld${EMULATION_NAME}_before_allocation. Those symbols are undefined.
As the result, bfd_elf_size_dynamic_sections will allocate
dynamic relocations for them, which leads to extra R_X86_64_NONE and
DT_TEXTREL on x86-64. On ia64, we got some R_IA64_REL64LSB instead of
R_IA64_NONE.


H.J.