Don't use cfmakeraw on SunOS

The cfmakeraw() function is an extension to POSIX and thus not fully
portable. It doesn't exist on Solaris and Illumos.
Source: http://www.perkin.org.uk/posts/solaris-portability-cfmakeraw.html

Change-Id: Icf514fe32c01e85baff2a0d49321e45a320703b7
Reviewed-by: Laszlo Papp <lpapp@kde.org>