[binutils-gdb] S/390: Fix segfault when linking -shared -nostartfiles

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 79c12faeea57e61364b6a7a3e411b096edce989c ***

Author: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Branch: master
Commit: 79c12faeea57e61364b6a7a3e411b096edce989c

S/390: Fix segfault when linking -shared -nostartfiles

Regression-tested on s390x.

bfd/ChangeLog:

2017-07-28  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* elf32-s390.c (elf_s390_finish_dynamic_sections): Add NULL
	pointer check for htab->elf.irelplt.
	* elf64-s390.c (elf_s390_finish_dynamic_sections): Likewise.