[lib][lwip] fix warning
[lib][lwip] fix warning

In file included from lk/lib/lwip/include/ipv4/lwip/ip.h:39:0,
                 from lk/lib/lwip/core/ipv4/ip.c:42:
lk/lib/lwip/core/ipv4/ip.c: In function ‘ip_input’:
lk/lib/lwip/include/ipv4/lwip/ip_addr.h:200:39: warning: the comparison will always evaluate as ‘false’ for the address of ‘current_iphdr_src’ will never be NULL [-Waddress]
 #define ip_addr_isany(addr1) ((addr1) == NULL || (addr1)->addr == IPADDR_ANY)
                                       ^
lk/lib/lwip/core/ipv4/ip.c:473:24: note: in expansion of macro ‘ip_addr_isany’
   if (check_ip_src && !ip_addr_isany(&current_iphdr_src))
                        ^

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