drivers/rtc/rtc-pl031.c: pass correct pointer to free_irq()

free_irq() expects the same pointer that was passed to request_irq(),
otherwise the IRQ is not freed.

The issue was found using the following coccinelle script:

  <smpl>
  @r1@
  type T;
  T devid;
  @@
  request_irq(..., devid)

  @r2@
  type r1.T;
  T devid;
  position p;
  @@
  free_irq@p(..., devid)

  @@
  position p != r2.p;
  @@
  *free_irq@p(...)
  </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>