Fix typos in documentation of bignum module
Found by doxygen.sh
@@ -644,7 +644,7 @@ int mbedtls_mpi_add_int( mbedtls_mpi *X, const mbedtls_mpi *A,
*
* \param X The destination MPI. This must point to an initialized MPI.
* \param A The minuend. This must point to an initialized MPI.
- * \param B The subtrahend.
+ * \param b The subtrahend.
*
* \return \c 0 if successful.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
@@ -817,7 +817,7 @@ int mbedtls_mpi_fill_random( mbedtls_mpi *X, size_t size,
*
* \param G The destination MPI. This must point to an initialized MPI.
* \param A The first operand. This must point to an initialized MPI.
- * \param A The second operand. This must point to an initialized MPI.
+ * \param B The second operand. This must point to an initialized MPI.
*
* \return \c 0 if successful.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.
