rand: improve error message for rand pool overflows

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from #22394)

(cherry picked from commit 0a8faac)

crypto/rand/rand_pool.c

@@ -257,7 +257,11 @@ size_t ossl_rand_pool_bytes_needed(RAND_POOL *pool, unsigned int entropy_factor)
 
     if (bytes_needed > pool->max_len - pool->len) {
         /* not enough space left */
-        ERR_raise(ERR_LIB_RAND, RAND_R_RANDOM_POOL_OVERFLOW);
+        ERR_raise_data(ERR_LIB_RAND, RAND_R_RANDOM_POOL_OVERFLOW,
+                       "entropy_factor=%u, entropy_needed=%zu, bytes_needed=%zu,"
+                       "pool->max_len=%zu, pool->len=%zu",
+                       entropy_factor, entropy_needed, bytes_needed,
+                       pool->max_len, pool->len);
         return 0;
     }