WIP: samsung-hero2lte: kernel update (3.18.140), use packaged exynos-dtbtool and enable wifi support

Self-explanatory, really.

The former of the two changes will have to be repeated to hero but I don't have an S7 flat to test, it should be fairly easy to port over (it's what I did for wifi support.)

Also went ahead and updated the downstream kernel since it was available.

device/device-samsung-hero2lte/APKBUILD

@@ -2,7 +2,7 @@
 pkgname="device-samsung-hero2lte"
 pkgdesc="Samsung Galaxy S7 edge"
 pkgver=0.1
-pkgrel=0
+pkgrel=1
 url="https://postmarketos.org"
 license="MIT"
 arch="aarch64"
@@ -10,6 +10,7 @@ options="!check !archcheck"
 depends="postmarketos-base linux-samsung-hero2lte mkbootimg mesa-dri-swrast msm-fb-refresher"
 makedepends="devicepkg-dev"
 source="deviceinfo initfs-hook.sh"
+subpackages="$pkgname-nonfree-firmware:nonfree_firmware"
 
 build() {
 	devicepkg_build $startdir $pkgname
@@ -21,6 +22,12 @@ package() {
 		"$pkgdir"/etc/postmarketos-mkinitfs/hooks/00-${pkgname}.sh
 }
 
+nonfree_firmware() {
+	pkgdesc="Non-free firmware for the Samsung Galaxy S7 (edge)"
+	depends="firmware-samsung-hero"
+	mkdir "$subpkgdir"
+}
+
 
 sha512sums="f780adfb37cbaa3930cb4eb4eef2b439c0b83d9a941a898f0396cb4120db4f5d5677903df8930bd3d234c7b6d5c3787f74f6133e2ccb4b04d5fa9d530aa34478  deviceinfo
 5a7be3cb8835ffb3783fcd4539de04f7f006c726ac9aea35cdca9e90b2877dc36cf4e314851bf9078f4b2dac061b7265866792d92a79f5232c56a0e17f7910b1  initfs-hook.sh"