ide: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

[bart: fix checkpatch.pl errors in ide-lib.c and ppc/mpc8xx.c while at it]

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>