lib/logic_iomem: Fix operation on 32-bit

On 32-bit, the first entry might be at 0/NULL, but that's
strange and leads to issues, e.g. where we check "if (ret)".
Use a IOREMAP_BIAS/IOREMAP_MASK of 0x80000000UL to avoid
this. This then requires reducing the number of areas (via
MAX_AREAS), but we still have 128 areas, which is enough.

Fixes: ca2e3342 ("lib: add iomem emulation (logic_iomem)")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

lib/logic_iomem.c

@@ -21,15 +21,15 @@ struct logic_iomem_area {
 
 #define AREA_SHIFT	24
 #define MAX_AREA_SIZE	(1 << AREA_SHIFT)
-#define MAX_AREAS	((1ULL<<32) / MAX_AREA_SIZE)
+#define MAX_AREAS	((1U << 31) / MAX_AREA_SIZE)
 #define AREA_BITS	((MAX_AREAS - 1) << AREA_SHIFT)
 #define AREA_MASK	(MAX_AREA_SIZE - 1)
 #ifdef CONFIG_64BIT
 #define IOREMAP_BIAS	0xDEAD000000000000UL
 #define IOREMAP_MASK	0xFFFFFFFF00000000UL
 #else
-#define IOREMAP_BIAS	0
-#define IOREMAP_MASK	0
+#define IOREMAP_BIAS	0x80000000UL
+#define IOREMAP_MASK	0x80000000UL
 #endif
 
 static DEFINE_MUTEX(regions_mtx);