Fix a performance problem with the new getnewbuf() code: in an outofspace condition ( bufspace > hibufspace ), an inappropriate scan of the empty queue was performed looking for buffer space to free up.
Fix a performance problem with the new getnewbuf() code: in an outofspace
condition ( bufspace > hibufspace ), an inappropriate scan of the empty
queue was performed looking for buffer space to free up.

Submitted by:	Matthew Dillon <dillon@apollo.backplane.com>

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase