Patch "Do not skip prologue for asm (.S) files" [1] changes GDB's
behaviour on which test gdb.arch/thumb-singlestep.exp depends, so
it causes the fail below:
(gdb) si^M
37 blx foo^M
(gdb) FAIL: gdb.arch/thumb-singlestep.exp: step into foo
the test assumes the program will stop at the instruction after "push"
but it doesn't. The fix to this fail is to do one more single step.
[1] https://sourceware.org/ml/gdb-patches/2015-06/msg00561.html
gdb/testsuite:
2015-07-07 Yao Qi <yao.qi@linaro.org>
* gdb.arch/thumb-singlestep.exp: Do one more single step.
