Makefiles: Reflow and align at 72 for comfort

[ziaee]

Summary

Much of the base system, including the rules for commit messages, is
wrapped at 72 so that it's comfortable in a traditional 80 character
console with line numbering. Wrap and align these files at 72 where
convenient to increase comfort and consistency. Minor touch-ups to
some comments as well.

If you hate this, no problem, no hard feelings!

Test Plan

+ Read the patched files
+ Make the targets

[ziaee]

increase capitalization and punctuation consistency

[ziaee]

Ping

[vladlen]

Is it necessary to decrease line length? The style(9) states:

This  file specifies the	preferred style	for kernel source files	in the
FreeBSD source tree.  It	is also	a guide	 for  the  preferred  userland
code style.  The	preferred line width is	80 characters, but some	excep-
tions  are  made	 when  a  slightly longer line is clearer or easier to
read.

I think, 80 chars length is acceptable.

[ziaee]

It isn't actually wrapped at 80. Most of the document is wrapped at 73, which is extremely annoying when using line numbering because many lines takes two lines for one extra character.

[ziaee]

rebase