Fix kotlin nullable errors in Settings

Fix kotlin nullable errors that were exposed by setting the retention
of android.annotation.NonNull and android.annotation.Nullable to
class retention.

Bug: 294110802
Test: builds
Change-Id: I6aa0516fa4f6443b6d4dff873baf3b08ff9189f0
Merged-In: I6aa0516fa4f6443b6d4dff873baf3b08ff9189f0
(cherry picked from commit 84f8961e67)

src/com/android/settings/RegulatoryInfoDisplayActivity.kt

@@ -46,7 +46,7 @@ class RegulatoryInfoDisplayActivity : Activity() {
 
         getRegulatoryInfo()?.let {
             val view = layoutInflater.inflate(R.layout.regulatory_info, null)
-            val image = view.findViewById<ImageView>(R.id.regulatoryInfo)
+            val image = view.requireViewById<ImageView>(R.id.regulatoryInfo)
             image.setImageDrawable(it)
             builder.setView(view)
             builder.show()