device-purism-librem5dev: configure getty using deviceinfo_getty variable (!796)

Move getty configuration from the .post-install script to deviceinfo.

device/device-purism-librem5dev/APKBUILD

@@ -2,7 +2,7 @@
 pkgname="device-purism-librem5dev"
 pkgdesc="Purism Librem 5 Devkit"
 pkgver=0.8
-pkgrel=1
+pkgrel=2
 url="https://postmarketos.org"
 license="MIT"
 arch="aarch64"
@@ -47,7 +47,7 @@ package() {
 	devicepkg_package $startdir $pkgname
 }
 
-sha512sums="020c10d969c95b9d6fc7d2d245c0586c5f35aa9e13164bbf2a4ec65b410342323f4bbc03b1fb7ad3abc69682b6e73f83b86583026c214ecff2c58c2c853f84e7  deviceinfo
+sha512sums="65087052e7d18b5378f4c01594ed430a8c8533df836de89b0fa73aa0980bc5bc43b8865a530bdbefaa4e7df8351fd44fabac11265b70e259e318a9113acc53d9  deviceinfo
 79abf8de1035418220c1d9168b038df10e06f23def18c944c065846dc5c4f5da66e8e62ae7ce9f5804ef064b0832d0b938f0e11e68878f203c322b05eb0ed639  uboot-script.cmd
 d10531ad6646ad6cfaf8ee1b0cc38f4e5e2eb39599251b75f25e954f1105761d5480d92cbe06ad52560207b883439071db89b19babf046a810360bd07c52c655  modprobe.d_rsi.conf
 5fdf45859f2bb154bcfe7c7341de4d5b239ef43d3f865e30456af073a8ee9d6682515c7e1dd52ddbe3969669d60689ba93c08ead32aadcfb164ff72a02b2e1a4  00-mesa.sh

device/device-purism-librem5dev/device-purism-librem5dev.post-install

@@ -1,6 +1,4 @@
 #!/bin/sh
-## Run getty on serial port
-sed -i -e "s/#ttyS0::respawn:\/sbin\/getty -L ttyS0 115200 vt100/ttymxc0::respawn:\/sbin\/getty -L ttymxc0 115200 vt100/" /etc/inittab
 
 # Enable GPS support
 rc-update add gpsd default

device/device-purism-librem5dev/deviceinfo

@@ -22,6 +22,7 @@ deviceinfo_dev_keyboard=""
 deviceinfo_no_framebuffer="true"
 # The following is required since this device has builtin ethernet
 deviceinfo_disable_dhcpd="true"
+deviceinfo_getty="ttymxc0;115200"
 
 # Bootloader related
 deviceinfo_flash_method="uuu"