turny: fix SPI/GPIO config for newer kernels

- Add complete config.txt settings with u-boot boot lines + spi=on
- Override sdImage.populateFirmwareCommands to use configtxt module output
- Mount firmware partition and add activation script to sync config.txt
- Load spi_bcm2835 and bcm2835_gpiomem kernel modules
- Add udev rule for gpiomem subsystem (not just gpio)
- Relax ProtectKernelTunables so service can access GPIO
- Update turny flake input to rppal-based CS pin fix

secrets/mosquitto/mokkimaatti.age

@@ -1,9 +1,9 @@
 age-encryption.org/v1
--> ssh-ed25519 osOCZA rqLqt3IrvBiIXneOWHFLJ3sBz3+dmNsl8LO6whM3Y2s
-5MSFsCQoaF97Ve6ossfYA+JezYy5Rod3Se4/y1kl7Go
--> ssh-ed25519 DFiohQ 33r7cd+b7CKR2rVcPFlRIVwcLfHrEgXgD/bD//86IG4
-Jg/Nripa9RCtbXaS+1vHBwVBG2q3VMi56lnhEnZvqmo
--> ssh-ed25519 PT7ffg uEatAaPQspVG41/O6d1oTkvhZUn2Au1TeJOlxBaVsXA
-0IATY8BEgVuVpYneH12F59Y+wIxnTh4QOTTajbQmWgY
---- 22zYI0N7UXX09jMLZ6FXgXaeijamAiKWVSv02kF/HKY
-9$éN[”mÞŽò–ñN’fîq)`qgúÐÃnÏÅ?„˜	Ô1’«õs,´ü°u(x…µf Ŷ¨é›[\‘£vø:ÉákµòƒB1½ƒlš+5ß[Ûò莠¹
5ðž<æió1gÿ!ÆEµ8SŠ ¶xü.kÔaÒƒ�NåáãÍÁ‹ìÿN­
+-> ssh-ed25519 osOCZA xdLLgxnXF6YwP6PA158Jk5PLd9DqMdD7iWzgxcig5ks
+mmjqlmU/6MyTaLUD63nyubvr+62SWik0a5wnlhuLQXY
+-> ssh-ed25519 DFiohQ BbxdetgH/z1ZUmzdKYLYFbSPx9y6vhqwZmMwlwRuCWM
+IpNVv3/EtML29RT9Ca8zrWM8gnGfk2iweW5RnXrTm94
+-> ssh-ed25519 PT7ffg f2BPj7TYxAnf1Os/VgMmxQ8g7DIhMdohUUe5y97WK1A
+zmNAbvgrV3tYQ8ZylZZ2P8v5FW7kklQt7XIkPqeIY9k
+--- 5RXgn5pqVJqKRAiZ9aA5uVL83P7fJHAs98R/iUC3tLs
+Ÿòb÷q§ÇA‰3ÇÒDâ”&kâK±Lï‰,û§|¤(�Àn8·žH‚'Q-µùJ$”ãÐZ°Ò�ïÓµ␍²�ûÀ¾ b;ˆ¾ññ Ñt®ç?Eÿ.±Ï=š�’E`åy£ÀcOËAc�ÍUt¨A.Úºýsº57¢²—CÖMÖemš‡÷˜ö ô