Fix RUNNER_CHILD_TEST framework.

Fix RUNNER_CHILD_TEST framework.

Fixes:
 * Add support for Ignore macro in child process. Now parent process
   print result in corrent way.
 * Fix SIGPIPE problem when test process want to use function write with stdout
   or stderr in RUNNER_CHILD_TEST. (Problem occures only when
   environment value DPL_USE_OLD_STYLE_LOGS=1 was defined).

[Issue#]   N/A
[Problem]  Macro RUNNER_IGNORE_MSG was not allowed in child test process.
           Call write(stdout, ...) in RUNNER_CHILD_TEST cause SIGPIPE.
[Cause]    Lack of support exception "TestRunner::Ignored"
           Lack of stdout and stderr descriptor in child process.
[Solution] Add support for Exception "TestRunner::Ignored" in RUNNER_CHILD_TEST

Change-Id: I7f69972ed6d2f6fea16584058c29acd9c8f0a27a