Get rid of major/minor number distinction.

Get rid of major/minor number distinction.

As of FreeBSD 6, devices can only be opened through devfs. These device
nodes don't have major and minor numbers anymore. The st_rdev field in
struct stat is simply based a copy of st_ino.

Simply display device numbers as hexadecimal, using "%#jx". This is
allowed by POSIX, since it explicitly states things like the following
(example taken from ls(1)):

	"If the file is a character special or block special file, the
	size of the file may be replaced with implementation-defined
	information associated with the device in question."

This makes the output of these commands more compact. For example, ls(1)
now uses approximately four columns less. While there, simplify the
column length calculation from ls(1) by calling snprintf() with a NULL
buffer.

Don't be afraid; if needed one can still obtain individual major/minor
numbers using stat(1).