[PATCH] Configure: recognize arm64 machine name as a synonym for aarch64

[Sergey Kandaurov]

# HG changeset patch
# User Sergey Kandaurov <pluknet at nginx.com>
# Date 1651239481 -14400
#      Fri Apr 29 17:38:01 2022 +0400
# Node ID 35afae4b3dffff6718c0cab3ceb16b9de207c20a
# Parent  a736a7a613ea6e182ff86fbadcb98bb0f8891c0b
Configure: recognize arm64 machine name as a synonym for aarch64.

In particular, this sets a reasonable cacheline size on FreeBSD and macOS,
which prefer to use this name and both lack _SC_LEVEL1_DCACHE_LINESIZE.

diff --git a/auto/os/conf b/auto/os/conf
--- a/auto/os/conf
+++ b/auto/os/conf
@@ -110,7 +110,7 @@ case "$NGX_MACHINE" in
         NGX_MACH_CACHE_LINE=64
     ;;
 
-    aarch64 )
+    aarch64 | arm64)
         have=NGX_ALIGNMENT value=16 . auto/define
         NGX_MACH_CACHE_LINE=64
     ;;