build: set DESTCPU correctly for 'make binary' on Apple Silicon

PR-URL: #40147
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Michael Dawson <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: Richard Lau <[email protected]>
Backport-PR-URL: #41855

Author: cheister

Makefile

@@ -825,6 +825,9 @@ else
 ifeq ($(findstring s390,$(UNAME_M)),s390)
 DESTCPU ?= s390
 else
+ifeq ($(findstring arm64,$(UNAME_M)),arm64)
+DESTCPU ?= arm64
+else
 ifeq ($(findstring arm,$(UNAME_M)),arm)
 DESTCPU ?= arm
 else
@@ -844,6 +847,7 @@ endif
 endif
 endif
 endif
+endif
 ifeq ($(DESTCPU),x64)
 ARCH=x64
 else