This patch cleans up MISRA C violations in the IO driver files.  Some
things did not make sense to fix or would require sweeping changes
but the simple issues have been resolved.

Defects Fixed

File                        Line Rule
drivers/io/io_fip.c         39   MISRA C-2012 Rule 5.6 (required)
drivers/io/io_fip.c         52   MISRA C-2012 Rule 8.9 (advisory)
drivers/io/io_fip.c         60   MISRA C-2012 Rule 5.9 (advisory)
drivers/io/io_fip.c         285  MISRA C-2012 Rule 8.9 (advisory)
drivers/io/io_fip.c         336  MISRA C-2012 Rule 15.4 (advisory)
drivers/io/io_fip.c         340  MISRA C-2012 Rule 15.4 (advisory)
drivers/io/io_fip.c         342  MISRA C-2012 Rule 15.4 (advisory)
drivers/io/io_memmap.c      30   MISRA C-2012 Rule 5.6 (required)
drivers/io/io_memmap.c      32   MISRA C-2012 Rule 5.9 (advisory)
drivers/io/io_memmap.c      85   MISRA C-2012 Rule 11.8 (required)
drivers/io/io_semihosting.c 66   MISRA C-2012 Rule 11.8 (required)
drivers/io/io_storage.c     73   MISRA C-2012 Rule 5.9 (advisory)
drivers/io/io_storage.c     116  MISRA C-2012 Rule 13.4 (advisory)

Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: Id9b1b2b684588d4eaab674ed4ed04f3950dd21f4