fix newlines in platform/platform_family
fix newlines in platform/platform_family

follows the pattern used by all the other plugins to strip off
the newlines (not sure why we don't just use .chomp, but i'm being
consistent with all the rest of the code)

mattray/ohai,phreakocious/ohai,davide125/ohai,shtzr840329/ohai,acaiafa/ohai,jaymzh/ohai,jseely/ohai,zshuo/ohai,btm/ohai,adamleff/ohai,chef/ohai,tas50/ohai-1,shtzr840329/ohai,davide125/ohai,bougyman/ohai,Fodoj/ohai,glennmatthews/ohai,nathwill/ohai,sh9189/ohai,glennmatthews/ohai,jbfavre/ohai,cmluciano/ohai,Juniper/ohai,juliandunn/ohai,n-marton/ohai,zshuo/ohai,jseely/ohai,http-418/ohai,tas50/ohai-1,numericillustration/ohai,sh9189/ohai,bougyman/ohai,johnbellone/ohai,dreamnite/ohai,higanworks/ohai,nathwill/ohai,http-418/ohai,adamleff/ohai,phreakocious/ohai,acaiafa/ohai,n-marton/ohai,higanworks/ohai,numericillustration/ohai,btm/ohai,criteo-forks/ohai,jbfavre/ohai,criteo-forks/ohai,cmluciano/ohai,Juniper/ohai,johnbellone/ohai,jaymzh/ohai,375gnu/ohai,mattray/ohai,dreamnite/ohai,Fodoj/ohai,juliandunn/ohai,375gnu/ohai,chef/ohai