xtensa: ptrace: Remove zero-length alignment array

Use a compiler attribute to align the areg field to 16 bytes instead of
using a zero-length alignment array.

Signed-off-by: Thorsten Blum <[e-mail]>
Message-Id: <[e-mail]>
Signed-off-by: Max Filippov <[e-mail]>

arch/xtensa/include/asm/ptrace.h

···
 	/* Additional configurable registers that are used by the compiler. */
 	xtregs_opt_t xtregs_opt;
 
-	/* Make sure the areg field is 16 bytes aligned. */
-	int align[0] __attribute__ ((aligned(16)));
-
 	/* current register frame.
 	 * Note: The ESF for kernel exceptions ends after 16 registers!
 	 */
-	unsigned long areg[XCHAL_NUM_AREGS];
+	unsigned long areg[XCHAL_NUM_AREGS] __aligned(16);
 };
 
 # define arch_has_single_step()	(1)