dietpi-patches: move forward Armbian base-files patch

We enforced the downgrade only in case the Armbian repo was left in place, unintentionally one conditional too deep. Re-apply with DietPi v9.20 entirely unconditionally, aside of the impossibly high package version of course. But lower that one as well to >=15 to catch even possibly ancient cases. Latest Debian base-files is 14 until after Forky release in summer 2027. Even if then someone runs into this patch on Debian 15 Duke somehow, it will be just a noop, no harm.

Author: MichaIng

.update/patches

@@ -2245,10 +2245,6 @@ Patch_9_16()
 		fi
 	fi
 
-	# Remove obsolete configs from pre-patches
-	[[ -f '/etc/apt/preferences.d/dietpi-armbian-tmp' ]] && G_EXEC rm /etc/apt/preferences.d/dietpi-armbian-tmp
-	[[ -f '/etc/apt/apt.conf.d/dietpi-armbian-tmp' ]] && G_EXEC rm /etc/apt/apt.conf.d/dietpi-armbian-tmp
-
 	# NanoPi 4/5/6 series: Repair faulty all component
 	if [[ $G_HW_MODEL =~ ^(68|76|79)$ && -f '/etc/apt/sources.list.d/dietpi.list' ]] && grep -Eq ' all .*/(legacy|vendor|current|edge)$' /etc/apt/sources.list.d/dietpi.list
 	then
@@ -2653,6 +2649,10 @@ Patch_9_19()
 
 Patch_9_20()
 {
+	# Remove obsolete configs from pre-patches
+	[[ -f '/etc/apt/preferences.d/dietpi-armbian-tmp' ]] && G_EXEC rm /etc/apt/preferences.d/dietpi-armbian-tmp
+	[[ -f '/etc/apt/apt.conf.d/dietpi-armbian-tmp' ]] && G_EXEC rm /etc/apt/apt.conf.d/dietpi-armbian-tmp
+
 	# Software updates, migrations and patches
 	if [[ -f '/boot/dietpi/.installed' ]]
 	then

.update/pre-patches

@@ -462,17 +462,6 @@ Package: armbian-firmware* linux-*
 Pin: origin apt.armbian.com
 Pin-Priority: 500
 _EOF_'
-			# Block and enforce downgrade of Armbian's base-files package to Debian's: https://github.com/MichaIng/DietPi/issues/6227#issuecomment-1713688577
-			if dpkg --compare-versions "$(dpkg-query -Wf '${Version}' base-files)" gt 20
-			then
-				G_DIETPI-NOTIFY 2 'Enforcing downgrade of Armbian'\''s base-files package to Debian'\''s'
-				G_EXEC eval 'cat << '\''_EOF_'\'' > /etc/apt/preferences.d/dietpi-armbian-tmp
-Package: base-files
-Pin: release o=Debian
-Pin-Priority: 1000
-_EOF_'
-				G_EXEC eval 'echo '\''APT::Get::Allow-Downgrades "1";'\'' > /etc/apt/apt.conf.d/dietpi-armbian-tmp'
-			fi
 		fi
 	fi
 
@@ -599,5 +588,21 @@ _EOF_"
 	fi
 fi
 
+# v9.20
+if (( $G_DIETPI_VERSION_CORE < 9 || ( $G_DIETPI_VERSION_CORE == 9 && $G_DIETPI_VERSION_SUB < 20 ) ))
+then
+	# Enforce downgrade of Armbian's base-files package to Debian's: https://github.com/MichaIng/DietPi/issues/6227#issuecomment-1713688577
+	if dpkg --compare-versions "$(dpkg-query -Wf '${Version}' base-files)" ge 15
+	then
+		G_DIETPI-NOTIFY 2 'Enforcing downgrade of Armbian'\''s base-files package to Debian'\''s'
+		G_EXEC eval 'cat << '\''_EOF_'\'' > /etc/apt/preferences.d/dietpi-armbian-tmp
+Package: base-files
+Pin: release o=Debian
+Pin-Priority: 1000
+_EOF_'
+		G_EXEC eval 'echo '\''APT::Get::Allow-Downgrades "1";'\'' > /etc/apt/apt.conf.d/dietpi-armbian-tmp'
+	fi
+fi
+
 exit 0
 }