The previous implementation of the error addition interface did not comply
with the invasive testing architecture guidelines. This commit fixes that
by:
- Renaming functions/macros/variables to follow the mbedtls_error_xxx or
mbedtls_test_hook_xxx convention.
- Making mbedtls_test_hook_error_add a global variable that can be set
by the testing code.
- Using a static inline function call, as opposed to macro, to keep
discrepancies between debug and production version to a minimum.
Signed-off-by: Chris Jones <christopher.jones@arm.com>