ioctl: fix RAE bit on last Get Log Page command

ioctl: fix RAE bit on last Get Log Page command

If nvme_get_log_page() requires multiple Get Log Page commands
because the total log length exceeds the transfer length,
args->rae is overwritten, causing the RAE bit to be set in all commands.
Retrieve the value of args->rae before overwriting it
so the RAE bit is set as requested in the last command.

Fixes: c23dbd4 ("linux: Change nvme_get_log_page to use nvme_get_log_args parm")
Signed-off-by: Caleb Sander <csander@purestorage.com>