In support of PR418: Make sure that -lpthread gets added to LIBS variable which puts it at the end of the tools' link commands, if libpthread.a is found.
In support of PR418:
Make sure that -lpthread gets added to LIBS variable which puts it at the
end of the tools' link commands, if libpthread.a is found.

Add a test for pthread.h so we can use #ifdef HAVE_PTHREAD_H


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@22401 91177308-0d34-0410-b5e6-96231b3b80d8

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