ACPICA: Cleanup byte/word/dword extraction macros, fix possible warnings

Removed unnecessary masking. For the 64-bit macros, removed
the structure overlay. Fixes aliasing warnings seen with gcc 4+
compilers.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

include/acpi/actypes.h

@@ -429,20 +429,12 @@ typedef unsigned long long acpi_integer;
 
 /* Data manipulation */
 
-#define ACPI_LOWORD(l)                  ((u16)(u32)(l))
-#define ACPI_HIWORD(l)                  ((u16)((((u32)(l)) >> 16) & 0xFFFF))
-#define ACPI_LOBYTE(l)                  ((u8)(u16)(l))
-#define ACPI_HIBYTE(l)                  ((u8)((((u16)(l)) >> 8) & 0xFF))
-
-/* Full 64-bit integer must be available on both 32-bit and 64-bit platforms */
-
-struct acpi_integer_overlay {
-	u32 lo_dword;
-	u32 hi_dword;
-};
-
-#define ACPI_LODWORD(integer)           (ACPI_CAST_PTR (struct acpi_integer_overlay, &integer)->lo_dword)
-#define ACPI_HIDWORD(integer)           (ACPI_CAST_PTR (struct acpi_integer_overlay, &integer)->hi_dword)
+#define ACPI_LOBYTE(integer)            ((u8)   (u16)(integer))
+#define ACPI_HIBYTE(integer)            ((u8) (((u16)(integer)) >> 8))
+#define ACPI_LOWORD(integer)            ((u16)  (u32)(integer))
+#define ACPI_HIWORD(integer)            ((u16)(((u32)(integer)) >> 16))
+#define ACPI_LODWORD(integer64)         ((u32)  (u64)(integer64))
+#define ACPI_HIDWORD(integer64)         ((u32)(((u64)(integer64)) >> 32))
 
 #define ACPI_SET_BIT(target,bit)        ((target) |= (bit))
 #define ACPI_CLEAR_BIT(target,bit)      ((target) &= ~(bit))