fix and cleanup suseconds_t/timeval stuff (broken on 64-bit)

trash in the upper 32 bits was making the kernel sleep forever in
select on 64-bit systems.

arch/x86_64/bits/alltypes.h.sh

@@ -55,7 +55,7 @@ TYPEDEF unsigned long uintptr_t;
 
 TYPEDEF long time_t;
 TYPEDEF long suseconds_t;
-STRUCT timeval { time_t tv_sec; int tv_usec; };
+STRUCT timeval { time_t tv_sec; long tv_usec; };
 STRUCT timespec { time_t tv_sec; long tv_nsec; };
 
 TYPEDEF int pid_t;