e1_input: fix compilation warning in e1_set_pcap_fd

  CC     e1_input.lo
e1_input.c: In function 'e1_set_pcap_fd':
e1_input.c:143:6: warning: variable 'ret' set but not used [-Wunused-but-set-variable]

e1_set_pcap_fd returns now the result of write. OpenBSC is still
assuming that this function returns nothing, so it simply ignores
this return value by now.
2 files changed