Fix typos found by Jeremiah Willcock.

This commit was SVN r23909.

ompi/mpi/man/man3/MPI_File_iwrite.3in

@@ -78,7 +78,7 @@ All other fields of
 .I status 
 are undefined.
 .sp
-It is erroneous to call this function if MPI_MODE_SEQENTIAL mode was specified when the file was open. 
+It is erroneous to call this function if MPI_MODE_SEQUENTIAL mode was specified when the file was open. 
 
 .SH ERRORS
 Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ functions do not return errors. If the default error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will be used to throw an MPI::Exception object.

ompi/mpi/man/man3/MPI_File_iwrite_at.3in

@@ -88,7 +88,7 @@ All other fields of
 .I status 
 are undefined. The request structure can be passed to MPI_Wait or MPI_Test, which will return a status with the number of bytes actually accessed. 
 .sp
-It is erroneous to call this function if MPI_MODE_SEQENTIAL mode was specified when the file was open. 
+It is erroneous to call this function if MPI_MODE_SEQUENTIAL mode was specified when the file was open. 
 
 .SH FORTRAN 77 NOTES
 .ft R