verbs_usnic: previous commit missed a symbol

0715802f52c24c236700ac085090d5441524644c missed that there is a call
to a common/verbs_usnic symbol in the common/verbs component.  This
call needs to be compiled out when the common/verbs_usnic component is
not built.

opal/mca/common/verbs/common_verbs_basics.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012-2015 Cisco Systems, Inc.  All rights reserved.
+ * Copyright (c) 2012-2016 Cisco Systems, Inc.  All rights reserved.
  *
  * $COPYRIGHT$
  *
@@ -21,7 +21,9 @@
 #include <unistd.h>
 #endif
 
+#if OPAL_COMMON_VERSION_USNIC_HAPPY
 #include "opal/mca/common/verbs_usnic/common_verbs_usnic.h"
+#endif
 
 /* This is crummy, but <infiniband/driver.h> doesn't work on all
    platforms with all compilers.  Specifically, trying to include it
@@ -91,12 +93,14 @@ int opal_common_verbs_fork_test(void)
     }
 #endif
 
+#if OPAL_COMMON_VERBS_USNIC_HAPPY
     /* Now register any necessary fake libibverbs drivers.  We
        piggyback loading these fake drivers on the fork test because
        they must be loaded before ibv_get_device_list() is invoked.
        Note that this routine is in a different common component (see
        comments over there for an explanation why).  */
     opal_common_verbs_usnic_register_fake_drivers();
+#endif
 
     return ret;
 }

opal/mca/common/verbs_usnic/configure.m4

@@ -54,21 +54,26 @@ AC_DEFUN([MCA_opal_common_verbs_usnic_COMPILE_MODE], [
 # ------------------------------------------------
 AC_DEFUN([MCA_opal_common_verbs_usnic_CONFIG],[
     AC_CONFIG_FILES([opal/mca/common/verbs_usnic/Makefile])
-    common_verbs_usnic_happy="no"
+    common_verbs_usnic_happy=0
 
     AC_ARG_WITH(verbs-usnic,
                 AC_HELP_STRING([--with-verbs-usnic],
                                [Add support in Open MPI to defeat a seemingly dire warning message from libibverbs that Cisco usNIC devices are not supported.  This support is not compiled by default because you can also avoid this libibverbs bug by installing the libibverbs_usnic "no no" plugin, available from https://github.com/cisco/libusnic_verbs or in binary form from cisco.com]))
 
     AS_IF([test "$with_verbs_usnic" = "yes"],
-          [common_verbs_usnic_happy=yes])
+          [common_verbs_usnic_happy=1])
 
-    AS_IF([test "$common_verbs_usnic_happy" = "yes"],
+    AS_IF([test $common_verbs_usnic_happy -eq 1],
           [OPAL_CHECK_OPENFABRICS([common_verbs_usnic],
-                                  [common_verbs_usnic_happy="yes"])
+                                  [common_verbs_usnic_happy=1],
+                                  [common_verbs_usnic_happy=0])
           ])
 
-    AS_IF([test "$common_verbs_usnic_happy" = "yes"],
+    AC_DEFINE_UNQUOTED([OPAL_COMMON_VERBS_USNIC_HAPPY],
+                       [$common_verbs_usnic_happy],
+                       [Whether the common/usnic_verbs component is being built or not])
+
+    AS_IF([test $common_verbs_usnic_happy -eq 1],
           [$1],
           [$2])