[BusyBox] remove type for RESERVE_BB_BUFFER defines

[Glenn McGrath]

Glenn McGrath wrote:
> 
> 
> If we took out the type we could make it
> #ifdef BB_FEATURE_BUFFERS_GO_ON_STACK
> #define RESERVE_BB_BUFFER(buffer,len)   char buffer[len]
> #else
> #define RESERVE_BB_BUFFER(buffer,len)   *buffer=xmalloc(len)
> #endif
> 

i meant
If we took out the type we could make it
#ifdef BB_FEATURE_BUFFERS_GO_ON_STACK
#define RESERVE_BB_BUFFER(buffer,len)   buffer[len]
#else
#define RESERVE_BB_BUFFER(buffer,len)   *buffer=xmalloc(len)
#endif