platform/x86: apple-gmux: Fix iomem_base __iomem annotation

Fix the __iomem annotation of the iomem_base pointers in the apple-gmux
code. The __iomem should go before the *.

This fixes a bunch of sparse warnings like this one:

drivers/platform/x86/apple-gmux.c:224:48: sparse:
 expected void const [noderef] __iomem *
 got unsigned char [usertype] *

Fixes: 0c18184d ("platform/x86: apple-gmux: support MMIO gmux on T2 Macs")
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202304040401.IMxt7Ubi-lkp@intel.com/Suggested-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Orlando Chamberlain <orlandoch.dev@gmail.com>
Link: https://lore.kernel.org/r/20230404111955.43266-1-hdegoede@redhat.com

drivers/platform/x86/apple-gmux.c

@@ -57,7 +57,7 @@
 struct apple_gmux_config;
 
 struct apple_gmux_data {
-	u8 *__iomem iomem_base;
+	u8 __iomem *iomem_base;
 	unsigned long iostart;
 	unsigned long iolen;
 	const struct apple_gmux_config *config;

include/linux/apple-gmux.h

@@ -66,7 +66,7 @@ static inline bool apple_gmux_is_indexed(unsigned long iostart)
 
 static inline bool apple_gmux_is_mmio(unsigned long iostart)
 {
-	u8 *__iomem iomem_base = ioremap(iostart, 16);
+	u8 __iomem *iomem_base = ioremap(iostart, 16);
 	u8 val;
 
 	if (!iomem_base)