Snippets for sipgrep 2.2.4 from Alpine riscv64

Sourced from https://build.alpinelinux.org/buildlogs/build-edge-riscv64/testing/sipgrep/sipgrep-2.2.4-r0.log.

• sipparse.c:43:12: warning: comparison of distinct pointer types lacks a cast [-Wcompare-distinct-pointer-types]
     43 |   for (; s < end; s++) {
        |            ^
  

• sipgrep.c:477:5: warning: 'pcap_lookupdev' is deprecated: use 'pcap_findalldevs' and use the first device [-Wdeprecated-declarations]
    477 |     char *dev = usedev ? usedev : pcap_lookupdev (pc_err);
        |     ^~~~
  

• sipgrep.c:644:11: warning: passing argument 1 of 'free' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
    644 |     free (match_data);
        |           ^~~~~~~~~~