asf4-drivers: Make utils_assert.h compatible with newer compilers

In the new toolchain `assert` is defined as a macro. That interferes
with the ASF function called `assert` so we undefined it right before
that function is defined.

Author: NickeZ

external/asf4-drivers/hal/utils/include/utils_assert.h

@@ -44,6 +44,8 @@
 #ifndef _ASSERT_H_INCLUDED
 #define _ASSERT_H_INCLUDED
 
+#undef assert
+
 #ifdef __cplusplus
 extern "C" {
 #endif