The loop should initialize only existing subindexes. Assuming that every
time there are CO_PDO_MAX_MAPPED_ENTRIES subindexes results in the
function returning CO_ERROR_OD_PARAMETERS because the call to
OD_get_u32() to read a non-existing subindex returns ODR_SUB_NOT_EXIST.
User can now enable extension callbacks in RPDO/TPDO handling paths
simply by configuration flags instead of modifying sources or by passing
the defines directly to the compiler.
* Merge two parts of CO_PDO_receive() into single common code
* Add CO_RPDO_initCallbackPre() for received RPDO messages
This optional mechanism allows to immediatelly wake the thread that
processes RPDO, without waiting for its next tick.
* Add CO_SYNC_initCallbackPre() for received SYNC messages
This optional mechanism allows to immediatelly wake the thread that
processes SYNC, without waiting for its next tick.
