mkimg: Add maximum capacity option

[manu]

Summary

mkimg: Add -C argument to specify maximum capacity

Add a -C option to specify a maximum capacity for the final image file.
It is useful to control the size of the generated image for sdcard or
when we will add dynamic size partition.

Sponsored By: Gandi.net

Test Plan

Create a bunch of image with different size etc ...

[wblock]

usr.bin/mkimg/mkimg.1

40 ↗

(On Diff #27751)

The space in "minimum capacity" makes it look like two arguments are expected. Maybe minimum_capacity or min_capacity instead? Likewise for "maximum capacity".

131 ↗

(On Diff #27751)

Passive -> active:
s/can be/is/

132 ↗

(On Diff #27751)

This is unclear, mostly due to "it" being nonspecific. Also has some passive stuff, so an attempted rewrite:

If the combined sizes of the given partitions exceed the size given with
.Fl C ,
image creation fails.

137 ↗

(On Diff #27751)

s/short hand/shorthand/

[manu]

Update manpage to address wblock@ comments.

[marcel]

usr.bin/mkimg/mkimg.c

391 ↗

(On Diff #27823)

This should be greater-than (>) instead of greater-equal (>=), don't you think?

[manu]

end block can be equal to the max capacity

[marcel]

LGTM. Thanks!

[wblock]

usr.bin/mkimg/mkimg.1

131 ↗

(On Diff #27911)

Whoops, didn't see the obvious change:

option specifies a maximum capacity for the disk image.