Mark aarch64 as BINARY=64

This opts us in to things like automatically building `openblas64_.so` on `aarch64` systems, which seems more consistent.

Author: staticfloat

Make.inc

@@ -747,6 +747,7 @@ endif
 ifneq (,$(findstring aarch64,$(ARCH)))
 OPENBLAS_DYNAMIC_ARCH:=0
 OPENBLAS_TARGET_ARCH:=ARMV8
+BINARY=:64
 endif
 
 # Set MARCH-specific flags