iio: adc: rcar-gyroadc: Cast pointer to uintptr_t to fix warning on 64-bit

On 64-bit:

drivers/iio/adc/rcar-gyroadc.c: In function 'rcar_gyroadc_parse_subdevs':
drivers/iio/adc/rcar-gyroadc.c:352:15: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
childmode = (unsigned int)of_id->data;
^

Cast the pointer to uintptr_t instead of unsigned int to fix this.

Signed-off-by: Geert Uytterhoeven <[e-mail]>
Reviewed-by: Simon Horman <[e-mail]>
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/adc/rcar-gyroadc.c

···
 			continue;
 		}
 
-		childmode = (unsigned int)of_id->data;
+		childmode = (uintptr_t)of_id->data;
 		switch (childmode) {
 		case RCAR_GYROADC_MODE_SELECT_1_MB88101A:
 			sample_width = 12;