device-oneplus-bacon: switch to lk2nd-msm8974 (MR 5691)

Switch to lk2nd-msm8974 because separate appended
dtb image build is not needed anymore.

device/testing/device-oneplus-bacon/APKBUILD

 # Reference: <https://postmarketos.org/devicepkg>
 pkgname=device-oneplus-bacon
 pkgver=4
-pkgrel=0
+pkgrel=1
 pkgdesc="OnePlus One"
 url="https://postmarketos.org"
 arch="armv7"
 license="MIT"
 depends="
-	lk2nd-msm8974-appended
+	lk2nd-msm8974
 	mkbootimg
 	postmarketos-base
 	"