dracut-functions.sh:print_vars() fix for values with spaces

for a variable with spaces, e.g.:
EXT_KEYMAPS='backspace keypad euro2'

The following would occur:
print_vars: eval printf -v _value %s '$EXT_KEYMAPS'
print_vars: printf -v _value %s backspace keypad euro2
print_vars: [[ -n backspacekeypadeuro2 ]]
print_vars: printf '%s=\"%s\"\n' EXT_KEYMAPS backspacekeypadeuro2

Thanks to Sebastian Köln for the fix!

dracut-functions.sh

@@ -225,7 +225,7 @@ print_vars() {
 
     for _var in "$@"
     do
-        eval printf -v _value "%s" "\$$_var"
+        eval printf -v _value "%s" \""\$$_var"\"
         [[ ${_value} ]] && printf '%s="%s"\n' "$_var" "$_value"
     done
 }