minor nit in fcntl

[Lou Salkind]

Index:	sys/sys/kern_descrip.c 4.2BSD

Description:
	If you try fcntl(fd, F_DUPFD, NOFILE), you get the error
	EMFILE instead of EINVAL.
Repeat-By:
	fcntl(fd, F_DUPFD, NOFILE);
Fix:
	In fcntl, replace the test
		if (i < 0 || i > NOFILE)
	by
		if (i < 0 || i >= NOFILE)

	Like I said, a minor nit.