linux-user: convert sockaddr_ll from host to target

As we convert sockaddr for AF_PACKET family for sendto() (target to
host) we need also to convert this for getsockname() (host to target).

arping uses getsockname() to get the the interface address and uses
this address with sendto().

Tested with:

    /sbin/arping -D -q -c2 -I eno1 192.168.122.88

...
getsockname(3, {sa_family=AF_PACKET, proto=0x806, if2,
pkttype=PACKET_HOST, addr(6)={1, 10c37b6b9a76}, [18]) = 0
...
sendto(3, "..." 28, 0,
       {sa_family=AF_PACKET, proto=0x806, if2, pkttype=PACKET_HOST,
       addr(6)={1, ffffffffffff}, 20) = 28
...
Signed-off-by: NLaurent Vivier <laurent@vivier.eu>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

linux-user/syscall.c

@@ -100,6 +100,7 @@ int __clone2(int (*fn)(void *), void *child_stack_base,
 #include <linux/route.h>
 #include <linux/filter.h>
 #include <linux/blkpg.h>
+#include <netpacket/packet.h>
 #include <linux/netlink.h>
 #ifdef CONFIG_RTNETLINK
 #include <linux/rtnetlink.h>
@@ -1383,6 +1384,10 @@ static inline abi_long host_to_target_sockaddr(abi_ulong target_addr,
         struct sockaddr_nl *target_nl = (struct sockaddr_nl *)target_saddr;
         target_nl->nl_pid = tswap32(target_nl->nl_pid);
         target_nl->nl_groups = tswap32(target_nl->nl_groups);
+    } else if (addr->sa_family == AF_PACKET) {
+        struct sockaddr_ll *target_ll = (struct sockaddr_ll *)target_saddr;
+        target_ll->sll_ifindex = tswap32(target_ll->sll_ifindex);
+        target_ll->sll_hatype = tswap16(target_ll->sll_hatype);
     }
     unlock_user(target_saddr, target_addr, len);