The function-like macro is
#define ARRAYSIZE(_Array) ((sizeof(_Array)) / (sizeof(_Array[0])))
The error shown is:
Error[Pm154]: in the definition of a function-like macro, each instance of a parameter shall be enclosed in parenthesis (MISRA C 2004 rule 19.10)
It's just pedantically saying that you should be doing this sizeof( (_Array)[0] ). Postfix operators have very high precedence so it's unlikely to become an actual problem.
Pedantically you should also use 0u since the intention is for the 0 to correspond to an unsigned type (size_t).
Also please note that leading underscore followed by upper-case letter is reserved for any use in the C language, MISRA or no MISRA.
I'd replace this whole macro with:
#define ARRAY_SIZE(array) ( sizeof(array) / sizeof *(array) )
Should be compliant both to the C language and MISRA-C.
