rm cannot recursively delete directory on tmpfs on RPi2

[Jia-Shiun Li]

amd64 and RPi3 do not have this issue.

jsli at rpi2:/home/jsli 13:04 # uname -a
FreeBSD rpi2 13.0-CURRENT FreeBSD 13.0-CURRENT r341419 GENERIC-NODEBUG  arm
jsli at rpi2:/home/jsli 13:05 # mount -t tmpfs tmpfs /mnt
jsli at rpi2:/home/jsli 13:05 # cd /mnt
jsli at rpi2:/mnt 13:05 # tar xf
/usr/ports/distfiles/sqlite-autoconf-3260000.tar.gz
jsli at rpi2:/mnt 13:05 # rm -rf sqlite-autoconf-3260000/
rm: sqlite-autoconf-3260000/tea: Operation not permitted
rm: sqlite-autoconf-3260000/: Directory not empty
jsli at rpi2:/mnt 13:05 #

-Jia-Shiun