ACPI: fix empty macros found by -Wextra

ACPI has a ton of macros which make a bunch of empty if's when configured
in non-debug mode.

[lenb: The code it complaines about is functionally correct,
 so this patch is just to make -Wextra happier]

#define DBG()

if(...)
        DBG();
next_c_statement

which turns into
if(...) ;
next_c_statement
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

drivers/acpi/glue.c

@@ -16,7 +16,7 @@
 #if ACPI_GLUE_DEBUG
 #define DBG(x...) printk(PREFIX x)
 #else
-#define DBG(x...)
+#define DBG(x...) do { } while(0)
 #endif
 static LIST_HEAD(bus_type_list);
 static DECLARE_RWSEM(bus_type_sem);

include/acpi/acmacros.h

@@ -599,26 +599,26 @@
 #define ACPI_DEBUG_EXEC(a)
 #define ACPI_NORMAL_EXEC(a)             a;
 
-#define ACPI_DEBUG_DEFINE(a)
-#define ACPI_DEBUG_ONLY_MEMBERS(a)
-#define ACPI_FUNCTION_NAME(a)
-#define ACPI_FUNCTION_TRACE(a)
-#define ACPI_FUNCTION_TRACE_PTR(a,b)
-#define ACPI_FUNCTION_TRACE_U32(a,b)
-#define ACPI_FUNCTION_TRACE_STR(a,b)
-#define ACPI_FUNCTION_EXIT
-#define ACPI_FUNCTION_STATUS_EXIT(s)
-#define ACPI_FUNCTION_VALUE_EXIT(s)
-#define ACPI_FUNCTION_ENTRY()
-#define ACPI_DUMP_STACK_ENTRY(a)
-#define ACPI_DUMP_OPERANDS(a,b,c,d,e)
-#define ACPI_DUMP_ENTRY(a,b)
-#define ACPI_DUMP_TABLES(a,b)
-#define ACPI_DUMP_PATHNAME(a,b,c,d)
-#define ACPI_DUMP_RESOURCE_LIST(a)
-#define ACPI_DUMP_BUFFER(a,b)
-#define ACPI_DEBUG_PRINT(pl)
-#define ACPI_DEBUG_PRINT_RAW(pl)
+#define ACPI_DEBUG_DEFINE(a)		do { } while(0)
+#define ACPI_DEBUG_ONLY_MEMBERS(a)	do { } while(0)
+#define ACPI_FUNCTION_NAME(a)		do { } while(0)
+#define ACPI_FUNCTION_TRACE(a)		do { } while(0)
+#define ACPI_FUNCTION_TRACE_PTR(a,b)	do { } while(0)
+#define ACPI_FUNCTION_TRACE_U32(a,b)	do { } while(0)
+#define ACPI_FUNCTION_TRACE_STR(a,b)	do { } while(0)
+#define ACPI_FUNCTION_EXIT		do { } while(0)
+#define ACPI_FUNCTION_STATUS_EXIT(s)	do { } while(0)
+#define ACPI_FUNCTION_VALUE_EXIT(s)	do { } while(0)
+#define ACPI_FUNCTION_ENTRY()		do { } while(0)
+#define ACPI_DUMP_STACK_ENTRY(a)	do { } while(0)
+#define ACPI_DUMP_OPERANDS(a,b,c,d,e)	do { } while(0)
+#define ACPI_DUMP_ENTRY(a,b)		do { } while(0)
+#define ACPI_DUMP_TABLES(a,b)		do { } while(0)
+#define ACPI_DUMP_PATHNAME(a,b,c,d)	do { } while(0)
+#define ACPI_DUMP_RESOURCE_LIST(a)	do { } while(0)
+#define ACPI_DUMP_BUFFER(a,b)		do { } while(0)
+#define ACPI_DEBUG_PRINT(pl)		do { } while(0)
+#define ACPI_DEBUG_PRINT_RAW(pl)	do { } while(0)
 
 #define return_VOID                     return
 #define return_ACPI_STATUS(s)           return(s)