fix missing max_align_t definition on aarch64

arch/aarch64/bits/alltypes.h.in

@@ -16,6 +16,8 @@ TYPEDEF unsigned int nlink_t;
 TYPEDEF float float_t;
 TYPEDEF double double_t;
 
+TYPEDEF struct { long long __ll; long double __ld; } max_align_t;
+
 TYPEDEF long time_t;
 TYPEDEF long suseconds_t;