IOMUX: Fix access past end of console_devices

We should only access console_devices[file][i] once we have checked that i
< cd_count[file]. Otherwise, we will access uninitialized memory at the end
of the loop. console_devices[file][i] should not be NULL, but putting the
assignment in the loop condition allows us to ensure that i is checked
beforehand. This isn't a bug, but it does make valgrind stop complaining.

Fixes: 400797ca ("IOMUX: Split out for_each_console_dev() helper macro")
Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Andrew Scull <ascull@google.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>