This patch adds a new test case which uses gdb.arch/insn-reloc.c too
to test displaced stepping. Nowadays, tests are for x86, x86_64 and
aarch64.
gdb/testsuite:
2015-10-12 Yao Qi <yao.qi@linaro.org>
* gdb.arch/disp-step-insn-reloc.exp: New test case.