[patch] Skip gdb.base/moribund-step.exp if displaced stepping is not supported

[Tom Tromey]

>>>>> "Yao" == Yao Qi <yao@codesourcery.com> writes:

Yao> Displaced stepping is needed to run moribund-step.exp correctly,
Yao> however, displaced stepping is not supported all ports.  This patch is
Yao> to check the target triplet to know displaced stepping is supported or
Yao> not.  Skip moribund-step.exp if not.

Yao> OK for mainline?

Looks good to me.  Ok.  Thanks for doing this.

Tom