r340343 triggers kernel assertion if file is opened with O_BENEATH flag set through symlink

Following test case triggers assertion after r340343:


#include <fcntl.h>

int
main(int argc, char **argv)
{
        openat(open("/etc", O_RDONLY), "termcap", O_RDONLY | O_BENEATH);
}

It results in:

panic: Assertion (ndp->ni_lcf & NI_LCF_LATCH) != 0 failed at
/usr/src/sys/kern/vfs_lookup.c:182