remove per-arch definitions for va_list

now that commit f7f1079796 removed the
legacy i386 conditional definition, va_list is in no way
arch-specific, and has no reason to be in the future. move it to the
shared part of alltypes.h.in

include/alltypes.h.in

@@ -60,6 +60,9 @@ TYPEDEF struct { unsigned __attr[2]; } pthread_rwlockattr_t;
 STRUCT _IO_FILE { char __x; };
 TYPEDEF struct _IO_FILE FILE;
 
+TYPEDEF __builtin_va_list va_list;
+TYPEDEF __builtin_va_list __isoc_va_list;
+
 TYPEDEF struct __mbstate_t { unsigned __opaque1, __opaque2; } mbstate_t;
 
 TYPEDEF struct __locale_struct * locale_t;