The value of vRtrMplsTpLsrFPInLabel specifies the forward path (FP)
ingress label used by the MPLS-TP LSR Path.
This object can be set only after vRtrMplsTpLsrFPEnabled is set to
'true'.
Once this object is set, the value may not be unset. To remove the
ingress label one must set vRtrMplsTpLsrFPEnabled to 'false'.