Use header file approach to detect Hypre in PETSc.
Use header file approach to detect Hypre in PETSc.

The previous approach was not working for PETSC_ARCH builds, but the
header file approach does seem to work well for that. We need to
ensure that the $petsc_have_hypre variable is initialized since we do
a -gt check on this rather than a string comparison.

capitalaslash/libmesh,giorgiobornia/libmesh,pbauman/libmesh,BalticPinguin/libmesh,capitalaslash/libmesh,90jrong/libmesh,90jrong/libmesh,dschwen/libmesh,hrittich/libmesh,dschwen/libmesh,BalticPinguin/libmesh,roystgnr/libmesh,pbauman/libmesh,jwpeterson/libmesh,hrittich/libmesh,BalticPinguin/libmesh,jwpeterson/libmesh,BalticPinguin/libmesh,libMesh/libmesh,jwpeterson/libmesh,dschwen/libmesh,hrittich/libmesh,libMesh/libmesh,hrittich/libmesh,hrittich/libmesh,giorgiobornia/libmesh,libMesh/libmesh,giorgiobornia/libmesh,BalticPinguin/libmesh,giorgiobornia/libmesh,capitalaslash/libmesh,dschwen/libmesh,pbauman/libmesh,90jrong/libmesh,dschwen/libmesh,capitalaslash/libmesh,90jrong/libmesh,jwpeterson/libmesh,libMesh/libmesh,giorgiobornia/libmesh,hrittich/libmesh,libMesh/libmesh,90jrong/libmesh,roystgnr/libmesh,libMesh/libmesh,pbauman/libmesh,jwpeterson/libmesh,BalticPinguin/libmesh,hrittich/libmesh,90jrong/libmesh,hrittich/libmesh,roystgnr/libmesh,roystgnr/libmesh,jwpeterson/libmesh,hrittich/libmesh,capitalaslash/libmesh,libMesh/libmesh,capitalaslash/libmesh,pbauman/libmesh,dschwen/libmesh,jwpeterson/libmesh,pbauman/libmesh,capitalaslash/libmesh,jwpeterson/libmesh,capitalaslash/libmesh,BalticPinguin/libmesh,roystgnr/libmesh,giorgiobornia/libmesh,giorgiobornia/libmesh,pbauman/libmesh,pbauman/libmesh,pbauman/libmesh,giorgiobornia/libmesh,90jrong/libmesh,BalticPinguin/libmesh,90jrong/libmesh,90jrong/libmesh,libMesh/libmesh,dschwen/libmesh,roystgnr/libmesh,roystgnr/libmesh,giorgiobornia/libmesh,dschwen/libmesh,roystgnr/libmesh