Cleanup of setfacl.c

[mhorne063_gmail.com]

Summary

Some cleanup changes to setfacl.c as briefly mentioned in D14934.

• Break the main() function into a couple more manageable sized pieces.

• Some small tweaks to follow style(9)

[emaste]

bin/setfacl/setfacl.c

70–73

It's not necessary to explicitly initialize these to false

[emaste]

bin/setfacl/setfacl.c

67

might as well make this a bool while here

74

also no need for whitespace between the global variables

77–79

generally these should be in alpha order

92

perhaps just stdin_files()

395–396

This is a tricky case; I'd prefer not to break a string in the middle (so that e.g. grep "cannot be less than zero" works to find the source of a message).

It looks a bit awkward but

errx(1,
    "%s: ...",
    optarg);

is probably best

[mhorne063_gmail.com]

Address review comments

Converted some existing global variables to bool

Made need_mask global variable static

Fixed prototype whitespace in setfacl.h