net: utils: net_pkt_hexdump() was missing log_strdup()
net: utils: net_pkt_hexdump() was missing log_strdup()

As the input string can be allocated from stack, we need to use
log_strdup() in net_pkt_hexdump() to print the extra string.

Signed-off-by: Jukka Rissanen <f9f077d1da4c7aa947f9864fa5a28c3588f6a45d@linux.intel.com>

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