configure: remove unused apply() function

Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

configure

@@ -1312,12 +1312,6 @@ check_host_cpp_condition(){
 EOF
 }
 
-apply(){
-    file=$1
-    shift
-    "$@" < "$file" > "$file.tmp" && mv "$file.tmp" "$file" || rm "$file.tmp"
-}
-
 cp_if_changed(){
     cmp -s "$1" "$2" && echo "$2 is unchanged" && return
     mkdir -p "$(dirname $2)"