x509: renaming of buffer variables in new serial setting function

Signed-off-by: Valerio Setti <vsetti@baylibre.com>
diff --git a/include/mbedtls/x509_crt.h b/include/mbedtls/x509_crt.h
index f88e8cc..56cc56b 100644
--- a/include/mbedtls/x509_crt.h
+++ b/include/mbedtls/x509_crt.h
@@ -1012,18 +1012,17 @@
 /**
  * \brief           Set the serial number for a Certificate.
  *
- * \param ctx               CRT context to use
- * \param serial_buff       A raw array of bytes containing the serial number
- *                          in big endian format
- * \param serial_buff_len   Length of the previous input buffer buffer
+ * \param ctx          CRT context to use
+ * \param serial       A raw array of bytes containing the serial number in big
+ *                     endian format
+ * \param serial_len   Length of the previous input buffer buffer
  *
  * \return          0 if successful, or
  *                  MBEDTLS_ERR_X509_BAD_INPUT_DATA if the provided input buffer
  *                  is too big (longer than MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN)
  */
 int mbedtls_x509write_crt_set_serial_new(mbedtls_x509write_cert *ctx,
-                                         unsigned char *serial_buff,
-                                         size_t serial_buff_len);
+                                         unsigned char *serial, size_t serial_len);
 
 /**
  * \brief           Set the validity period for a Certificate
diff --git a/library/x509write_crt.c b/library/x509write_crt.c
index da9ef6c..5cd1e30 100644
--- a/library/x509write_crt.c
+++ b/library/x509write_crt.c
@@ -131,15 +131,14 @@
 #endif // MBEDTLS_BIGNUM_C && !MBEDTLS_DEPRECATED_REMOVED
 
 int mbedtls_x509write_crt_set_serial_new(mbedtls_x509write_cert *ctx,
-                                         unsigned char *serial_buff,
-                                         size_t serial_buff_len)
+                                         unsigned char *serial, size_t serial_len)
 {
-    if (serial_buff_len > MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN) {
+    if (serial_len > MBEDTLS_X509_RFC5280_MAX_SERIAL_LEN) {
         return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
     }
 
-    ctx->serial_len = serial_buff_len;
-    memcpy(ctx->serial, serial_buff, serial_buff_len);
+    ctx->serial_len = serial_len;
+    memcpy(ctx->serial, serial, serial_len);
 
     return 0;
 }