hwloc: clarify the error message when infiniband/verbs.h is missing but hwloc's verbs support is requested

Signed-off-by: Brice Goglin <Brice.Goglin@inria.fr>

Author: bgoglin

Diff for: opal/mca/hwloc/external/external.h

@@ -57,7 +57,7 @@ BEGIN_C_DECLS
 #    if defined(HAVE_INFINIBAND_VERBS_H)
 #        include MCA_hwloc_external_openfabrics_header
 #    else
-#        error Tried to include hwloc verbs helper file, but hwloc was compiled with no OpenFabrics support
+#        error Tried to include hwloc verbs helper file, but <infiniband/verbs.h> is missing
 #    endif
 #endif
 

Diff for: opal/mca/hwloc/hwloc2/hwloc2.h

@@ -7,6 +7,7 @@
  * Copyright (c) 2017      Research Organization for Information Science
  *                         and Technology (RIST). All rights reserved.
  *
+ * Copyright (c) 2020      Inria.  All rights reserved.
  * $COPYRIGHT$
  *
  * Additional copyrights may follow
@@ -42,7 +43,7 @@ BEGIN_C_DECLS
 #    if defined(HAVE_INFINIBAND_VERBS_H)
 #        include "hwloc/include/hwloc/openfabrics-verbs.h"
 #    else
-#        error Tried to include hwloc verbs helper file, but hwloc was compiled with no OpenFabrics support
+#        error Tried to include hwloc verbs helper file, but <infiniband/verbs.h> is missing
 #    endif
 #endif