[CRM][MPLS] Fix the mpls nexthop CRM attribute (sonic-net#2008)

Author: smaheshm

orchagent/crmorch.cpp

@@ -64,7 +64,7 @@ const map<CrmResourceType, uint32_t> crmResSaiAvailAttrMap =
     { CrmResourceType::CRM_SNAT_ENTRY, SAI_SWITCH_ATTR_AVAILABLE_SNAT_ENTRY },
     { CrmResourceType::CRM_DNAT_ENTRY, SAI_SWITCH_ATTR_AVAILABLE_DNAT_ENTRY },
     { CrmResourceType::CRM_MPLS_INSEG, SAI_OBJECT_TYPE_INSEG_ENTRY },
-    { CrmResourceType::CRM_MPLS_NEXTHOP, SAI_OBJECT_TYPE_NEXT_HOP },
+    { CrmResourceType::CRM_MPLS_NEXTHOP, SAI_SWITCH_ATTR_AVAILABLE_IPV4_NEXTHOP_ENTRY },
 };
 
 const map<string, CrmResourceType> crmThreshTypeResMap =