Controlfile autobackup to disk outside ASM on RAC environment (11gR2)

 Recently I try to make several recovery test for a rac environment. Note 1472171.1 said controlfile autobackup (control file snapshot too) need to be on shared location for RAC instance, so when I run rman backup, I see controlfile autobackup is created on flash recovery area inside ASM.

I don't have shared filesystems to make a backup (acfs, nfs), the only shared storage is asm.

I use rman without catalog to make backups.

As part of my backups scripts, I backup archivelogs with this script (database script backup is similar):

configure controlfile autobackup format for device type disk to '+FRA/%F';