sparc64: fix sparc_ipc type conversion

__kernel_timespec and timespec are currently the same type, but once
they are different, the type cast has to be changed here.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/sparc/kernel/sys_sparc_64.c

@@ -344,7 +344,7 @@ SYSCALL_DEFINE6(sparc_ipc, unsigned int, call, int, first, unsigned long, second
 			goto out;
 		case SEMTIMEDOP:
 			err = sys_semtimedop(first, ptr, (unsigned int)second,
-				(const struct timespec __user *)
+				(const struct __kernel_timespec __user *)
 					     (unsigned long) fifth);
 			goto out;
 		case SEMGET: