device-oneplus-bacon: install lk2nd package (MR 4077)

This enables us to easily flash lk2nd with pmbootstrap during
installation.

device/testing/device-oneplus-bacon/APKBUILD

 # Reference: <https://postmarketos.org/devicepkg>
 pkgname=device-oneplus-bacon
 pkgver=2
-pkgrel=1
+pkgrel=2
 pkgdesc="OnePlus One"
 url="https://postmarketos.org"
 arch="armv7"
 license="MIT"
-depends="postmarketos-base mkbootimg"
+depends="
+	lk2nd-msm8974-appended
+	mkbootimg
+	postmarketos-base
+	"
 makedepends="devicepkg-dev"
 subpackages="
 	$pkgname-kernel-downstream:kernel_downstream