configure: cleanup: remove unused --datadir switch

Unused. mplayer-svn used it as fallback directory to locate the OSD
font, and for the GUI.

configure

@@ -512,9 +512,6 @@ for ac_option do
   --bindir=*)
     _bindir=$(echo $ac_option | cut -d '=' -f 2)
     ;;
-  --datadir=*)
-    _datadir=$(echo $ac_option | cut -d '=' -f 2)
-    ;;
   --mandir=*)
     _mandir=$(echo $ac_option | cut -d '=' -f 2)
     ;;
@@ -747,7 +744,6 @@ done
 
 # Atmos: moved this here, to be correct, if --prefix is specified
 test -z "$_bindir"  && _bindir="$_prefix/bin"
-test -z "$_datadir" && _datadir="$_prefix/share/mpv"
 test -z "$_mandir"  && _mandir="$_prefix/share/man"
 test -z "$_confdir" && _confdir="$_prefix/etc/mpv"
 test -z "$_localedir"  && _localedir="$_prefix/share/locale"
@@ -3150,7 +3146,6 @@ CONFIGURATION = $configuration
 
 prefix  = \$(DESTDIR)$_prefix
 BINDIR  = \$(DESTDIR)$_bindir
-DATADIR = \$(DESTDIR)$_datadir
 MANDIR  = \$(DESTDIR)$_mandir
 CONFDIR = \$(DESTDIR)$_confdir
 LOCALEDIR = \$(DESTDIR)$_localedir
@@ -3292,7 +3287,6 @@ cat > $TMPH << EOF
 
 #define CONFIGURATION "$configuration"
 
-#define MPLAYER_DATADIR "$_datadir"
 #define MPLAYER_CONFDIR "$_confdir"
 #define MPLAYER_LOCALEDIR "$_localedir"
 
@@ -3493,7 +3487,6 @@ cat << EOF
 Config files successfully generated by ./configure $configuration !
 
   Install prefix: $_prefix
-  Data directory: $_datadir
   Config direct.: $_confdir
 
   Enabled optional drivers: