zdtm/sigpending: check only relevant part of siginfo

Recently, a kernel behaviour how siginfo is copied into user-space was
changed:

4ce5f9c9e754 ("signal: Use a smaller struct siginfo in the kernel")

According to the rt_sigqueueinfo man page, the caller should set
si_code, si_pid, si_uid, si_value and there is no guarantee about other
fields.
Signed-off-by: Andrei Vagin <avagin@gmail.com>

test/zdtm/static/sigpending.c

@@ -46,9 +46,8 @@ typedef union cr_siginfo cr_siginfo_t;
 
 #define siginf_body(s) (&((cr_siginfo_t *)(s))->_info._sifields)
 
-#ifdef __i386__
 /*
- * On x86_32 kernel puts only relevant union member when signal arrives,
+ * The kernel puts only relevant union member when signal arrives,
  * leaving _si_fields to be filled with junk from stack. Check only
  * first 12 bytes:
  *	// POSIX.1b signals.
@@ -61,9 +60,6 @@ typedef union cr_siginfo cr_siginfo_t;
  * Look at __copy_siginfo_to_user32() for more information.
  */
 # define _si_fields_sz 12
-#else
-# define _si_fields_sz (sizeof(siginfo_t) - offsetof(cr_siginfo_t, _info._sifields))
-#endif
 #define siginfo_filled (offsetof(cr_siginfo_t, _info._sifields) + _si_fields_sz)
 
 static pthread_mutex_t exit_lock;