Remove unneeded check

The fix_quasi_reduction function changed to static so checking the
invalid arguments are not needed anymore.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
diff --git a/library/bignum_mod_raw_invasive.h b/library/bignum_mod_raw_invasive.h
index 7770c0a..3550eaf 100644
--- a/library/bignum_mod_raw_invasive.h
+++ b/library/bignum_mod_raw_invasive.h
@@ -43,8 +43,8 @@
  * \return      #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \p N is invalid.
  */
 MBEDTLS_STATIC_TESTABLE
-int mbedtls_mpi_mod_raw_fix_quasi_reduction(mbedtls_mpi_uint *X,
-                                            const mbedtls_mpi_mod_modulus *N);
+void mbedtls_mpi_mod_raw_fix_quasi_reduction(mbedtls_mpi_uint *X,
+                                             const mbedtls_mpi_mod_modulus *N);
 
 #endif /* MBEDTLS_TEST_HOOKS */