x264.c: add psy-rd string to modify psy-rd settings
x264.c: add psy-rd string to modify psy-rd settings

psy-rd should be default on when subme >= 6 (x264 library mentions
this), and I'm not sure how much this options is used in 'normal use'

xkfz007/vlc,vlc-mirror/vlc,xkfz007/vlc,krichter722/vlc,jomanmuk/vlc-2.1,vlc-mirror/vlc,shyamalschandra/vlc,jomanmuk/vlc-2.2,jomanmuk/vlc-2.2,vlc-mirror/vlc-2.1,shyamalschandra/vlc,jomanmuk/vlc-2.2,shyamalschandra/vlc,jomanmuk/vlc-2.1,jomanmuk/vlc-2.2,jomanmuk/vlc-2.1,vlc-mirror/vlc,jomanmuk/vlc-2.1,shyamalschandra/vlc,krichter722/vlc,xkfz007/vlc,vlc-mirror/vlc-2.1,xkfz007/vlc,vlc-mirror/vlc,jomanmuk/vlc-2.2,vlc-mirror/vlc,krichter722/vlc,vlc-mirror/vlc,vlc-mirror/vlc-2.1,shyamalschandra/vlc,jomanmuk/vlc-2.1,jomanmuk/vlc-2.1,vlc-mirror/vlc-2.1,vlc-mirror/vlc-2.1,vlc-mirror/vlc-2.1,krichter722/vlc,jomanmuk/vlc-2.2,vlc-mirror/vlc,xkfz007/vlc,vlc-mirror/vlc-2.1,xkfz007/vlc,shyamalschandra/vlc,krichter722/vlc,krichter722/vlc,krichter722/vlc,jomanmuk/vlc-2.1,shyamalschandra/vlc,xkfz007/vlc,jomanmuk/vlc-2.2