fs: dlm:Remove unneeded semicolon

Eliminate the following coccinelle check warning:
fs/dlm/midcomms.c:972:2-3

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Zhang Mingyu <zhang.mingyu@zte.com.cn>
Signed-off-by: David Teigland <teigland@redhat.com>