Add pacman hook for installing kernel in host.

pacman_hooks/hooks/90-dracut-install.hook

@@ -0,0 +1,12 @@
+[Trigger]
+Type = Path
+Operation = Install
+Operation = Upgrade
+Target = usr/lib/modules/*/pkgbase
+Target = usr/lib/dracut/*
+
+[Action]
+Description = Updating linux initcpios in host...
+When = PostTransaction
+Exec = /usr/share/libalpm/scripts/dracut-install
+NeedsTargets

pacman_hooks/scripts/dracut-install

@@ -0,0 +1,34 @@
+#!/bin/bash -e
+
+kernels=()
+dracut_update=0
+
+while read -r line; do
+    if [[ $line != 'usr/lib/modules/'+([^/])'/pkgbase' ]]; then
+		dracut_update=1 # Dracut files have been updated
+        continue 
+    fi
+
+    read -r pkgbase < "/${line}"
+	kernels+=("${pkgbase}")
+done
+
+if (( dracut_update )); then
+	kernels=()
+	for file in /lib/modules/*/pkgbase; do
+		if read -r pkgbase &> /dev/null < "$file"; then
+			kernels+=("${pkgbase}")
+		fi
+	done
+fi
+
+for kernel in "${kernels[@]}"; do
+	path="$(grep -lE "^${kernel}\$" /usr/lib/modules/*/pkgbase)"
+	version=$(basename "${path%/pkgbase}")
+    read -r pkgbase < "$path"
+
+    install -Dm0644 "/${path%'/pkgbase'}/vmlinuz" "/boot/vmlinuz-${pkgbase}"
+
+	echo ":: Building initramfs for $kernel-$version in host..."
+	chroot /var/host /bin/su -c "dracut -f \"/boot/initramfs-${kernel}.img\" --kver \"${version}\""
+done