(maybe) Async mode failures on PPC

[Luis Machado <luisgpm@linux.vnet.ibm.com>]

Hey guys,

I was giving a shot at the testsuite for PPC and some failures showed
up, related, apparently, to the async mode.

The pattern is like this, first there's a message informing you that the
"Target is running" and then no other commands will be accepted due to
"Cannot execute this command while the selected thread is running.".

Is this something we're still addressing or a new problem? Should we
modify the testcase so it becomes async-aware?

For example, this piece of the watchpoint.exp testcase

(gdb) PASS: gdb.base/watchpoint.exp: until to ival3 assignment
until^M
Target is executing.^M
(gdb) FAIL: gdb.base/watchpoint.exp: until out of loop
step^M
Cannot execute this command while the selected thread is running.^M

Regards,
Luis