Remove residual blank line at start of Makefile

This is a residual of the $FreeBSD$ removal.

MFC After: 3 days (though I'll just run the command on the branches)
Sponsored by: Netflix

Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

Remove residual blank line at start of Makefile

This is a residual of the $FreeBSD$ removal.

MFC After: 3 days (though I'll just run the command on the branches)
Sponsored by: Netflix

Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

Merge ^/head r319801 through r320041.

Add some initial basic tests for du(1)

Tests that exercise the following flags are added in this commit:
- -A
- -H
- -I
- -g
- -h
- -k
- -m

Additional tests will be added soon.

MFC after: 1 month

Merge ^/head r319801 through r320041.

Add some initial basic tests for du(1)

Tests that exercise the following flags are added in this commit:
- -A
- -H
- -I
- -g
- -h
- -k
- -m

Additional tests will be added soon.

MFC after: 1 month

Remove residual blank line at start of Makefile

This is a residual of the $FreeBSD$ removal.

MFC After: 3 days (though I'll just run the command on the branches)
Sponsored by: Netflix

Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

Merge ^/head r319801 through r320041.

Add some initial basic tests for du(1)

Tests that exercise the following flags are added in this commit:
- -A
- -H
- -I
- -g
- -h
- -k
- -m

Additional tests will be added soon.

MFC after: 1 month