accel/ivpu: Fix warning due to undefined CONFIG_PROC_FS

accel/ivpu: Fix warning due to undefined CONFIG_PROC_FS

Change #if to #ifdef CONFIG_PROC_FS to fix warning reported by test robot:
drivers/accel/ivpu/ivpu_drv.c:458:5: warning: "CONFIG_PROC_FS" is not defined, evaluates to 0 [-Wundef]

Fixes: 63cc028484ab ("accel/ivpu: Add fdinfo support for memory statistics")
Reviewed-by: Maciej Falkowski <maciej.falkowski@linux.intel.com>
Reviewed-by: Andrzej.Kacprowski@linux.intel.com
Signed-off-by: Karol Wachowski <karol.wachowski@linux.intel.com>
Link: https://patch.msgid.link/20251112071911.1136934-1-karol.wachowski@linux.intel.com