misc: rp1-pio: Back-port some 6.11 build fixes

Porting rp1-pio to rpi-6.11.y uncovered a few missing #includes and a
difference of const-ness. Although not needed here, back-porting the
resulting changes makes the driver more "correct" and may prevent a
future merge conflict.

Signed-off-by: Phil Elwell <[email protected]>

Author: pelwell

drivers/misc/rp1-pio.c

@@ -22,6 +22,9 @@
 #include <linux/init.h>
 #include <linux/ioctl.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pio_rp1.h>
+#include <linux/platform_device.h>
 #include <linux/rp1-firmware.h>
 #include <linux/semaphore.h>
 #include <linux/slab.h>

include/linux/pio_rp1.h

@@ -176,7 +176,7 @@ typedef rp1_pio_sm_config pio_sm_config;
 typedef struct rp1_pio_client *PIO;
 
 void pio_set_error(struct rp1_pio_client *client, int err);
-int pio_get_error(struct rp1_pio_client *client);
+int pio_get_error(const struct rp1_pio_client *client);
 void pio_clear_error(struct rp1_pio_client *client);
 
 int rp1_pio_can_add_program(struct rp1_pio_client *client, void *param);