gnu: openmpi: Pass explicit "--with-*" configure flags.

* gnu/packages/mpi.scm (openmpi)[arguments]: Pass "--with-ucx",
"--with-psm", and "--with-psm2".

gnu/packages/mpi.scm

@@ -204,6 +204,12 @@ (define-public openmpi
                            "--with-hwloc=external"
                            "--with-libevent"
 
+                           ;; Make sure ./configure fails if one of these is
+                           ;; missing.
+                           "--with-ucx"
+                           "--with-psm"
+                           "--with-psm2"
+
                            ;; InfiniBand support
                            "--enable-openib-control-hdr-padding"
                            "--enable-openib-dynamic-sl"