Fix yesno() implementation.

src/cdm

@@ -43,11 +43,12 @@ exiterror() { sleep 1; exit 1; }
 yesno()
 {
 	[ -z "$1" ] && return 1
+	eval value=\$${1}
 
-	case "$1" in
+	case "$value" in
 	    [Yy][Ee][Ss]|[Tt][Rr][Uu][Ee]|[Oo][Nn]|1) return 0;; 
 	    [Nn][Oo]|[Ff][Aa][Ll][Ss][Ee]|[Oo][Ff][Ff]|0) return 1;; 
-		*) warn "\`$1' is not a valid argument for \`yesno'; using \`no' for now."
+		*) warn "Invalid value for \`$1'; falling back to \`no' for now.";;
 	esac
 }