sftp_read: on EOF remove packet before flush
sftp_read: on EOF remove packet before flush

Since the sftp_packetlist_flush() function will move all the existing
FXP_READ requests in this handle to the zombie list we must first remove
this just received packet as it is clearly not a zombie.

libssh2/libssh2,libssh2/libssh2,libssh2/libssh2,libssh2/libssh2