Description: use generic march on arm64 when using 'default' machine
 When building for generic distribution we need a stable baseline
 architecture, or depending on the build worker the result will vary.
 
 Force the default flags if the user explicitly sets marchine=default
 at configuration time.
Author: Luca Boccassi <bluca@debian.org>
Forwarded: https://patches.dpdk.org/patch/49259/
--- a/config/arm/meson.build
+++ b/config/arm/meson.build
@@ -6,6 +6,7 @@
 march_opt = '-march=@0@'.format(machine)
 
 arm_force_native_march = false
+arm_force_default_march = machine == 'default'
 
 machine_args_generic = [
 	['default', ['-march=armv8-a+crc+crypto']],
@@ -102,7 +103,11 @@ else
 	cmd_generic = ['generic', '', '', 'default', '']
 	cmd_output = cmd_generic # Set generic by default
 	machine_args = [] # Clear previous machine args
-	if not meson.is_cross_build()
+	if arm_force_default_march and not meson.is_cross_build()
+		machine = impl_generic
+		cmd_output = cmd_generic
+		impl_pn = 'default'
+	elif not meson.is_cross_build()
 		# The script returns ['Implementer', 'Variant', 'Architecture',
 		# 'Primary Part number', 'Revision']
 		detect_vendor = find_program(join_paths(