[ARM] use __used attribute

Use the newly introduced __used attribute in place of the deprecated
__attribute_used__.  Functionally the same.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/include/asm-arm/mach/arch.h b/include/asm-arm/mach/arch.h
index fd2f9bf..c59fad1 100644
--- a/include/asm-arm/mach/arch.h
+++ b/include/asm-arm/mach/arch.h
@@ -49,7 +49,7 @@
  */
 #define MACHINE_START(_type,_name)			\
 static const struct machine_desc __mach_desc_##_type	\
- __attribute_used__					\
+ __used							\
  __attribute__((__section__(".arch.info.init"))) = {	\
 	.nr		= MACH_TYPE_##_type,		\
 	.name		= _name,