Add magiskboot to kernelsu working directory (#1684)

Add the magiskboot binary to the /data/adb/ksu/bin directory so that
scripts/programs can call magiskboot to patch the boot/init_boot image.

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Co-authored-by: weishu <twsxtd@gmail.com>

manager/app/src/main/java/me/weishu/kernelsu/ui/util/KsuCli.kt

@@ -84,7 +84,8 @@ fun execKsud(args: String, newShell: Boolean = false): Boolean {
 
 fun install() {
     val start = SystemClock.elapsedRealtime()
-    val result = execKsud("install", true)
+    val magiskboot = File(ksuApp.applicationInfo.nativeLibraryDir, "libmagiskboot.so").absolutePath
+    val result = execKsud("install --magiskboot $magiskboot", true)
     Log.w(TAG, "install result: $result, cost: ${SystemClock.elapsedRealtime() - start}ms")
 }