ypbind-mt: add status command for initscript

Add the "status" command in initscript to check the status of ypbind.
remove ypbind-yocto.init as ypbind.init, which is the initscript, make
its name similar to other recipes

Signed-off-by: Zhu Yanjun <yanjun.zhu@windriver.com>
Signed-off-by: Roy Li <rongqing.li@windriver.com>
Signed-off-by: Joe MacDonald <joe_macdonald@mentor.com>