Current zpool import code skips directory entries which have prefixes
similar to some system files on linux such as "fd", "core" etc. However,
this means one cannot have one's zpools hosted inside files which are named
e.g. core-1 or lp. Furthermore, apart from the string checks there is already
which makes the zpool_open_func work only with regular files and block devices.
To fix this problem remove most of the checks since they are redundant but
leave the checks for the 'hpet' and 'watchdog' names. Furthermore, change
the checks to strcmp which albeit less safe than strncmp allows to have
devices whose names are prefixed by 'hpet' or 'watchdog'.
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#4438