watchdog: lenovo_se30_wdt: include io.h for devm_ioremap()

After merging the watchdog tree, today's linux-next build (x86_64
allmodconfig) failed like this:

drivers/watchdog/lenovo_se30_wdt.c: In function 'lenovo_se30_wdt_probe':
drivers/watchdog/lenovo_se30_wdt.c:272:31: error: implicit declaration of function 'devm_ioremap' [-Wimplicit-function-declaration]
272 | priv->shm_base_addr = devm_ioremap(dev, base_phys, SHM_WIN_SIZE);
| ^~~~~~~~~~~~
drivers/watchdog/lenovo_se30_wdt.c:272:29: error: assignment to 'unsigned char *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
272 | priv->shm_base_addr = devm_ioremap(dev, base_phys, SHM_WIN_SIZE);
| ^

Caused by commit

c284153a2c55 ("watchdog: lenovo_se30_wdt: Watchdog driver for Lenovo SE30 platform")

Somewhere alogn the way a change to some include file means that
linux/io.h is no longer implicitly included. I have added the following
patch for today.

Fixes: c284153a2c55 ("watchdog: lenovo_se30_wdt: Watchdog driver for Lenovo SE30 platform")
Signed-off-by: Stephen Rothwell <[e-mail]>
Reviewed-by: Mark Pearson <[e-mail]>
Reviewed-by: Wim Van Sebroeck <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Guenter Roeck <[e-mail]>
Signed-off-by: Wim Van Sebroeck <[e-mail]>

drivers/watchdog/lenovo_se30_wdt.c

···
 
 #define dev_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/io.h>
 #include <linux/dmi.h>
 #include <linux/delay.h>
 #include <linux/iommu.h>