mpilib: use DIV_ROUND_UP and remove unused macros

Remove MIN, MAX and ABS macros that are duplicates kernel's native
implementation.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Chester Kener <Cl3Kener@gmail.com>

Conflicts:
	lib/mpi/mpicoder.c