Add wireguard patch instructions

arch-config/Dokumente/lineageos-build.md

@@ -34,6 +34,7 @@ max_size = 30G
 cache_dir = /var/lineageos-cache
 ```
 
+`$ export PATH="${PATH}:/home/exu/.local/bin"`
 `$ echo 'export USE_CCACHE=1' >> ~/.bashrc`  
 
 ### Install repo tool
@@ -63,12 +64,61 @@ Initialize the repo
 
 Sync repo content  
 This can take a long time  
-`$ repo sync --force-sync`  
+`$ repo sync`  
 
 Repo fetches the latest version automatically, so we can use a symlink  
 `$ ln -sf /var/lineageos-build/lineage/.repo/repo/repo ~/.local/bin/repo`  
 
-### Download device source files
+## Add Wireguard patch to kernel
+
+### Fetch source
+Create the file `(SRC_DIR)/.repo/local_manifests/wireguard.xml`  
+`(SRC_DIR)` is your `.../lineage/` directory  
+Make sure to replace `(KERNEL_DIR)` with your device's kernel directory.  
+For example `(SRC_DIR)/kernel/oneplus/msm8996`  
+```
+<?xml version="1.0" encoding="UTF-8"?>
+<manifest>
+	<remote name="zx2c4" fetch="https://git.zx2c4.com/" />
+	<project remote="zx2c4" name="wireguard-linux-compat" path="kernel/wireguard-linux-compat" revision="master" sync-s="true">
+		<linkfile src="src" dest="(KERNEL_DIR)/net/wireguard" />
+	</project>
+</manifest>
+
+```
+
+Run `repo sync`  
+
+### Add kernel patch
+Edit `(KERNEL_DIR)/net/Makefile`  
+```
+ obj-$(CONFIG_LLC)        += llc/
+ obj-$(CONFIG_NET)        += ethernet/ 802/ sched/ netlink/
+ obj-$(CONFIG_NETFILTER)  += netfilter/
++obj-$(CONFIG_WIREGUARD)  += wireguard/
+ obj-$(CONFIG_INET)       += ipv4/
+ obj-$(CONFIG_XFRM)       += xfrm/
+ obj-$(CONFIG_UNIX)       += unix/
+```
+
+Edit `(KERNEL_DIR)/net/Kconfig`  
+```
+ if INET
+ source "net/ipv4/Kconfig"
+ source "net/ipv6/Kconfig"
+ source "net/netlabel/Kconfig"
++source "net/wireguard/Kconfig"
+```
+
+Edit `(KERNEL_DIR)/arch/(ARCH)/configs/lineageos_(DEVICE)_defconfig`  
+
+```
+ CONFIG_L2TP=y
+ CONFIG_BRIDGE=y
++CONFIG_WIREGUARD=y
+```
+
+## Download device source files
 Activate the build environment  
 `$ . ./build/envsetup.sh`