Decompression failure of specific IPv4 stream with changing RND

The ROHC library fails to decompress the attached stream. It is one IPv4 stream with changing RND (RND=1 -> RND=0) and less than 5 bits of IP-ID delta to transmit.

As RND changed, the extension 3 is required. As there are some IP-ID bits to transmit, the UOR-2-ID packet is chosen. As there are less than 5 bits of IP-ID delta to transmit, the compressor puts these bits in the UOR-2-ID base header. Because the RND flag changed, the compressor also puts 16 bits of IP-ID delta in extension 3 (flag I=1). The decompressor fails to decompress such a packet because it receives more than 16 bits of IP-ID delta.

Solution:
 1/ at compressor, put zeroes in the 5 bits of the UOR-2-ID base header if RND flag changed in the last few packets.
 2/ at decompressor, warn about > 16 IP-ID bits but do not stop parsing, simply ignore superfluous bits.

For the 2nd point, stop parsing if ROHC_RFC_STRICT_DECOMPRESSOR is defined.