Just clear IB_CFG_DONE on receiving Peer config request when channel open

Just clear IB_CFG_DONE on receiving Peer config request when channel open

In current codes, while l2cap channel has been configured and in
CST_OPEN state, if local receives another configure request from
remote, config_done(IB_CFG_DONE and OB_CFG_DONE) will be cleared.
However, OB_CFG_DONE will be never set again. So, from then on,
data can not be transmitted to remote by this channel. To fix
this issue, we should just clear IB_CFG_DONE and keep OB_CFG_DONE
unchanged on receiving Peer config request when channel open

Change-Id: I8deca0c8ff73faafc3da94dcd9ea55e06bd8a31d
CRs-Fixed: 1059193