Change the return type to handle the case where an invalid interface name is passed to this function.

This commit was SVN r20933.

opal/util/if.c

@@ -865,7 +865,7 @@ int opal_ifnametoindex(const char* if_name)
  *  corresponding kernel index.
  */
 
-uint16_t opal_ifnametokindex(const char* if_name)
+int16_t opal_ifnametokindex(const char* if_name)
 {
     opal_if_t* intf;
     int rc = opal_ifinit();
@@ -1230,7 +1230,7 @@ opal_ifnametoindex(const char* if_name)
     return OPAL_ERR_NOT_SUPPORTED;
 }
 
-uint16_t
+int16_t
 opal_ifnametokindex(const char* if_name)
 {
     return OPAL_ERR_NOT_SUPPORTED;

opal/util/if.h

@@ -77,7 +77,7 @@ OPAL_DECLSPEC int opal_ifnametoindex(const char* if_name);
  *  @param if_name (IN)  Interface name
  *  @return              Interface kernel index
  */
-OPAL_DECLSPEC uint16_t opal_ifnametokindex(const char* if_name);
+OPAL_DECLSPEC int16_t opal_ifnametokindex(const char* if_name);
 
 /**
  *  Lookup an interface by opal_list index and return its kernel index.