scripts/checkstack.pl: Fix arm64 wrong or unknown architecture

[ Upstream commit 4f45d62a52297b10ded963412a158685647ecdec ]

The following error occurs for the `make ARCH=arm64 checkstack` case:

aarch64-linux-gnu-objdump -d vmlinux $(find . -name '*.ko') | \
perl ./scripts/checkstack.pl arm64
wrong or unknown architecture "arm64"

As suggested by Masahiro Yamada, fix the above error using regular
expressions in the same way it was fixed for the `ARCH=x86` case via
commit fda9f99 ("scripts/checkstack.pl: automatically handle
32-bit and 64-bit mode for ARCH=x86").

Suggested-by: Masahiro Yamada <[email protected]>
Signed-off-by: George G. Davis <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

Author: George G. Davis

Diff for: scripts/checkstack.pl

@@ -45,7 +45,7 @@
 	$x	= "[0-9a-f]";	# hex character
 	$xs	= "[0-9a-f ]";	# hex character or space
 	$funcre = qr/^$x* <(.*)>:$/;
-	if ($arch eq 'aarch64') {
+	if ($arch =~ '^(aarch|arm)64$') {
 		#ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp, #-80]!
 		$re = qr/^.*stp.*sp, \#-([0-9]{1,8})\]\!/o;
 	} elsif ($arch eq 'arm') {