move time_t and suseconds_t definitions to common alltypes.h.in

now that all 32-bit archs have 64-bit time_t (and suseconds_t), the
arch-provided _Int64 macro (long or long long, as appropriate) can be
used to define them, and arch-specific definitions are no longer
needed.

include/alltypes.h.in

@@ -8,6 +8,8 @@ TYPEDEF _Addr ssize_t;
 TYPEDEF _Addr intptr_t;
 TYPEDEF _Addr regoff_t;
 TYPEDEF _Reg register_t;
+TYPEDEF _Int64 time_t;
+TYPEDEF _Int64 suseconds_t;
 
 TYPEDEF signed char     int8_t;
 TYPEDEF signed short    int16_t;