EDAC/altera: Use the proper type for the IRQ status bits

Smatch complains about the cast of a u32 pointer to unsigned long:

  drivers/edac/altera_edac.c:1878 altr_edac_a10_irq_handler()
  warn: passing casted pointer '&irq_status' to 'find_first_bit()'

This code wouldn't work on a 64 bit big endian system because it would
read past the end of &irq_status.

 [ bp: massage. ]

Fixes: 13ab8448 ("EDAC, altera: Add ECC Manager IRQ controller support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thor Thayer <thor.thayer@linux.intel.com>
Cc: James Morse <james.morse@arm.com>
Cc: kernel-janitors@vger.kernel.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20190624134717.GA1754@mwanda