pmb.aportgen: Stop generating Maintainer: lines for device ports (MR 1932)

Most device ports that are added to pmaports (particularly the testing
category) are not actually "maintained". Many of them are never updated
after the initial contribution. There is little reason to list a
"Maintainer:" if the device package is actually not actively maintained
by that person.

Let's stop generating the Maintainer: line by default.
Instead, contributors should add the lines themselves if they are willing
to (actively) maintain the device package for a longer period of time.
Once they no longer want to maintain the package, the Maintainer:
line should be removed again.

pmb/aportgen/device.py

@@ -196,7 +196,6 @@ def generate_apkbuild(args, pkgname, name, arch, flash_method):
 
     # Whole APKBUILD
     content = f"""\
-        # Maintainer: Firstname Lastname <email> (CHANGEME!)
         # Reference: <https://postmarketos.org/devicepkg>
         pkgname={pkgname}
         pkgdesc="{name}"

pmb/aportgen/linux.py

@@ -25,7 +25,6 @@ def generate_apkbuild(args, pkgname, deviceinfo, patches):
 
     patches = ("\n" + " " * 12).join(patches)
     content = f"""\
-        # Maintainer: Firstname Lastname <email> (CHANGEME!)
         # Reference: <https://postmarketos.org/vendorkernel>
         # Kernel config based on: arch/{carch}/configs/(CHANGEME!)