Add Passwall Function

Follow the steps below to add the passwall function. The passwall function is not included in the default function and requires code modification and package download support.

Execute the following command under wigoridirectory:

echo "src-git passwall_packages https://github.com/xiaorouji/openwrt-passwall-packages.git;main" >> "feeds.conf.default"
echo "src-git passwall https://github.com/xiaorouji/openwrt-passwall.git;main" >> "feeds.conf.default"

Modify include/target.mk:

diff --git a/include/target.mk b/include/target.mk
index b5e3e7ff6f..f65e127ecf 100644
--- a/include/target.mk
+++ b/include/target.mk
@@ -53,7 +53,7 @@ DEFAULT_PACKAGES.nas:=\
        mdadm
 # For router targets
 DEFAULT_PACKAGES.router:=\
-       dnsmasq \
+       dnsmasq-full \

Download and install the package of passwall:

./scripts/feeds update -a
./scripts/feeds install -a
./scripts/feeds install -a -f -p PWpackages
./scripts/feeds install luci-app-passwall

Configure passwall and unconfigure dnsmasq：
1. Execute the following command to enter the menu configuration GUI:
```
make menuconfig
```
2. Configure passwall:
  OpenWrt Configuration > LuCI > 3. Application > luci-app-passwall
  Figure 1. Passwall
3. Unconfigure dnsmasq:
  OpenWrt Configuration > Base system > dnsmasq, dnsmasq-full
  Figure 2. Unconfigure Dnsmasq
4. Execute the following command to update and download software package:
```
make download V=s
```
5. Compilation:
```
make -j8
```
  Note: The compilation may take 2 hours.