[functions] Allow newlines (\n) in log messages

Allow caller to log messages with embedded newlines when calling
CT_DoLog and other logging functions (eg. CT_Abort...).

 reporter_name="Julien DUSSER"

 reporter_url="http://sourceware.org/ml/crossgcc/2008-10/msg00054.html"

 reporter_comment="Soft-float for the 405 PowerPC"