Unify BUFFER_SIZE settings for x86_64 again to fix potentially fatal mismatch in DYNAMIC_ARCH builds

common_x86_64.h

@@ -228,14 +228,8 @@ static __inline unsigned int blas_quickdivide(unsigned int x, unsigned int y){
 #define HUGE_PAGESIZE	( 2 << 20)
 
 #ifndef BUFFERSIZE
-#if defined(SKYLAKEX) 
-#define BUFFER_SIZE	(32 << 21)
-#elif defined(HASWELL) || defined(ZEN)
 #define BUFFER_SIZE	(32 << 22)
 #else
-#define BUFFER_SIZE	(32 << 20)
-#endif
-#else
 #define BUFFER_SIZE	(32 << BUFFERSIZE)
 #endif