[NFC] turn comment into static_assert (#71504)

Author: fmayer

compiler-rt/lib/sanitizer_common/sanitizer_ring_buffer.h

@@ -47,7 +47,9 @@ class RingBuffer {
   void push(T t) {
     *next_ = t;
     next_--;
-    // The condition below works only if sizeof(T) is divisible by sizeof(T*).
+    static_assert((sizeof(T) % sizeof(T *)) == 0,
+                  "The condition below works only if sizeof(T) is divisible by "
+                  "sizeof(T*).");
     if (next_ <= reinterpret_cast<T*>(&next_))
       next_ = last_;
   }