ebtables: enable KERNEL_64_USERSPACE_32 for arm

On arm64 board, run the kernel as 64bit with 32bit userpace ebtables, then run ebtables command:
ebtables -A OUTPUT -p arp -o eth3 -j DROP
Below error occurs:
kernel msg: ebtables bug: please report to author: Standard target size too big

To solve this, enable KERNEL_64_USERSPACE_32 for arm as the commit <ebtables: enable KERNEL_64_USERSPACE_32 for powerpc> do.

Use TARGET_ARCH to replace KARCH here because that KARCH can't always get value by default.

---
 meta-networking/recipes-filter/ebtables/ebtables_2.0.10-4.bb | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

index d5e7341..d89ee1a 100644
@@ -42,10 +42,10 @@ inherit update-rc.d systemd
 python __anonymous () {
     import re
 
-    karch = d.getVar('KARCH')
+    karch = d.getVar('TARGET_ARCH')
     multilib = d.getVar('MLPREFIX')
 
-    if multilib and karch == 'powerpc64':
+    if multilib and ( karch == 'powerpc64' or karch == 'arm' ):
         searchstr = "lib.?32"
         reg = re.compile(searchstr)
         if reg.search(multilib):

2.9.3