main/postmarketos-base: ship os-release (MR 1522)

Ship the /etc/os-release file from the postmarketos-base package instead
of having it generated by pmbootstrap.

main/postmarketos-base/APKBUILD

 pkgname=postmarketos-base
-pkgver=6
+pkgver=7
 pkgrel=0
 pkgdesc="Meta package for minimal postmarketOS base"
 url="https://postmarketos.org"
@@ -55,6 +55,7 @@ _source644="
 	etc/motd
 	etc/sleep-inhibitor.conf
 	etc/udev/rules.d/50-firmware.rules
+	etc/os-release
 	"
 _source755="
 	etc/init.d/deferred-initcalls
@@ -141,6 +142,7 @@ fe0651904c1f40ffa67d83daca190af199f63247e53642a59a1e1147cd06776fcf20b7b2fcc53737
 2989a2701d96c496bcdb536ce93984c75604e7b248d427f7b7106ea1946760549d4c29590257a598c9ad8d3fa88735d9b168dbda28c2294816065acdbab2e93f  rootfs-etc-motd
 041e50a7f78f7f03153175027439fc203f3dc81ed9970c579a16728d36e006e77f49b0321ee4bb7bb127fa6e4c31de3e7029f80ea75c4afc83bae7d24906372d  rootfs-etc-sleep-inhibitor.conf
 0b098828080055d3646ea54891cb0e1b578cbc30f5e16f7284f2814c08192f18079a38fb686d192715ae6a3d2cd6625d9e3cf99f234a6f0d94088bb0cb2ce43d  rootfs-etc-udev-rules.d-50-firmware.rules
+75451751862a084415212bf2f90fdb4dac6a75bb063a411e15c9060f8c7f0b0b8c994dd6ba964d00a249eb80f5a0665d9cfdf75923af6de47f9723b10e61e9a7  rootfs-etc-os-release
 5fd6dd7f9941e975a6ce559924eb252606943276dc09455bbeb05ff718ecd28f20a08eee8e04ca580e5af71d4c944c256ec04f07b07286394f5dfedfa59273e7  rootfs-etc-init.d-deferred-initcalls
 dadd251229eb5759e3cba77c39a4afc6f28bcbe0f272cd3ab41b7ff4fe6a3d2b9ee765e1a0b8f9241274e757ed3b2ce035ee5abe91843e55fb4188a3c401ca78  rootfs-etc-init.d-devmappings
 f5cc0f1265955d2646e5f099dd4b5d4c287945bfc18c16044db57670d456f55c678fc11cc59e6dab3fa340832ce869d516302a3a35c13518539ed0cedca51819  rootfs-etc-init.d-swapfile

main/postmarketos-base/rootfs-etc-os-release

+PRETTY_NAME="postmarketOS edge"
+NAME="postmarketOS"
+VERSION_ID="edge"
+VERSION="edge"
+ID="postmarketos"
+ID_LIKE="alpine"
+HOME_URL="https://www.postmarketos.org/"
+SUPPORT_URL="https://gitlab.com/postmarketOS"
+BUG_REPORT_URL="https://gitlab.com/postmarketOS/pmbootstrap/issues"