pmbootstrap aportgen device-*, linux-*: put one dependency on one line

in pmaports.git, oftentimes we put one dependency on one line if a package has multiple of those. The device package usually has a few, and the list of makedepends of a kernel is also quite long. Having them on their own lines makes new ports easier to review and generates a nicer diff when changing the depends.

Change:

depends="a b c"

to:

depends="
	a
	b
	c
"

and sort the list entries alphabetically.

Do this for:

• pmb/aportgen/device.py, depends (not makedepends as there is only one)
• pmb/aportgen/linux.py, makedepends (there is no depends)