doc: fix SSL_set0_rbio

Change-Id: I8559f1af23a2254ad5fe62c7169d71bd6c957384
Signed-off-by: Yuchen Dai <silentdai@gmail.com>
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/45024
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
diff --git a/include/openssl/ssl.h b/include/openssl/ssl.h
index 85d995a..7ff7e72 100644
--- a/include/openssl/ssl.h
+++ b/include/openssl/ssl.h
@@ -267,7 +267,7 @@
 // |SSL_set0_rbio| and |SSL_set0_wbio| instead.
 OPENSSL_EXPORT void SSL_set_bio(SSL *ssl, BIO *rbio, BIO *wbio);
 
-// SSL_set0_rbio configures |ssl| to write to |rbio|. It takes ownership of
+// SSL_set0_rbio configures |ssl| to read from |rbio|. It takes ownership of
 // |rbio|.
 //
 // Note that, although this function and |SSL_set0_wbio| may be called on the