fix missing return code

src/pmi/upmi/upmi.c: In function 'UPMI_GET_LOCAL_RANK':
src/pmi/upmi/upmi.c:746:1: error: control reaches end of non-void function [-Werror=return-type]
  746 | }
      | ^
src/pmi/upmi/upmi.c: In function 'UPMI_GET_LOCAL_SIZE':
src/pmi/upmi/upmi.c:764:1: error: control reaches end of non-void function [-Werror=return-type]
  764 | }
      | ^
src/pmi/upmi/upmi.c: In function 'UPMI_GET_LOWEST_RANK':
src/pmi/upmi/upmi.c:782:1: error: control reaches end of non-void function [-Werror=return-type]
  782 | }

Signed-off-by: Nicolas Morey-Chaisemartin <nmoreychaisemartin@suse.com>

src/pmi/upmi/upmi.c

@@ -742,6 +742,8 @@ int UPMI_GET_LOCAL_RANK(int rank, int *size) {
     }
     *size= val->data.uint16;
     return convert_err(rc);
+    #else
+	return 0;
     #endif
 }
 
@@ -760,6 +762,8 @@ int UPMI_GET_LOCAL_SIZE(int *size) {
     }
     *size= val->data.uint32;
     return convert_err(rc);
+    #else
+	return 0;
     #endif
 }
 
@@ -778,5 +782,7 @@ int UPMI_GET_LOWEST_RANK(int *rank) {
     }
     *rank= val->data.uint32;
     return convert_err(rc);
+    #else
+	return 0;
     #endif
 }