proper return value for MPI_File_call_errhandler

Lisandro Dalcin found we returned the wrong value from
MPI_File_call_errhandler.  it should return MPI_SUCCESS unless something
goes wrong with MPI_File_call_errhandler itself.

Closes #2259
Signed-off-by: Junchao Zhang <jczhang@mcs.anl.gov>

src/mpi/errhan/file_call_errhandler.c

@@ -95,7 +95,6 @@ int MPI_File_call_errhandler(MPI_File fh, int errorcode)
        not integers.  */
 
     if (e->handle == MPI_ERRORS_RETURN) {
-	mpi_errno = errorcode;
 	goto fn_exit;
     }
 

test/mpi/errhan/Makefile.am

@@ -20,6 +20,7 @@ noinst_PROGRAMS = \
     errfatal      \
     predef_eh     \
     errstring2    \
+    file_errhdl   \
     dynamic_errcode_predefined_errclass
 
 EXTRA_PROGRAMS = errcode errring errstring

test/mpi/errhan/file_errhdl.c

+/* test case contributed by Lisandro Dalcin <dalcinl@gmail.com> */
+#include <mpi.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+  int ierr;
+  MPI_File fh;
+  MPI_Init(&argc, &argv);
+
+  MPI_File_open(MPI_COMM_WORLD,"/tmp/datafile",
+                MPI_MODE_CREATE|MPI_MODE_RDWR|MPI_MODE_DELETE_ON_CLOSE,
+                MPI_INFO_NULL,&fh);
+
+  MPI_File_set_errhandler(fh,MPI_ERRORS_RETURN);
+  ierr = MPI_File_call_errhandler(fh,MPI_ERR_FILE);
+  if (ierr != MPI_SUCCESS) {
+      fprintf(stderr, "ierr: %d, expected: %d\n", ierr, (int)MPI_SUCCESS);
+  } else {
+      printf(" No Errors\n");
+  }
+  MPI_File_close(&fh);
+
+  MPI_Finalize();
+  return 0;
+}

test/mpi/errhan/testlist

@@ -5,3 +5,4 @@ predef_eh 1
 predef_eh 2
 errstring2 1
 dynamic_errcode_predefined_errclass 1
+file_errhdl 1