asm-generic: use compat version for preadv2 and pwritev2

Compat architectures that does not use generic unistd (mips, s390),
declare compat version in their syscall tables for preadv2 and
pwritev2. Generic unistd syscall table should do it as well.

[arnd: this initially slipped through the review and an
 incorrect patch got merged. arch/tile/ is the only architecture
 that could be affected for their 32-bit compat mode, every
 other architecture we support today is fine.]
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

include/uapi/asm-generic/unistd.h

@@ -718,9 +718,9 @@ __SYSCALL(__NR_mlock2, sys_mlock2)
 #define __NR_copy_file_range 285
 __SYSCALL(__NR_copy_file_range, sys_copy_file_range)
 #define __NR_preadv2 286
-__SYSCALL(__NR_preadv2, sys_preadv2)
+__SC_COMP(__NR_preadv2, sys_preadv2, compat_sys_preadv2)
 #define __NR_pwritev2 287
-__SYSCALL(__NR_pwritev2, sys_pwritev2)
+__SC_COMP(__NR_pwritev2, sys_pwritev2, compat_sys_pwritev2)
 
 #undef __NR_syscalls
 #define __NR_syscalls 288