testsuite, fortran: make kfail gfortran specific

The modified test in function-calls.exp actually passes with ifort and
ifx.  The particular fail seems to be specific to gfortran.  When the
test was introduced it was only tested with gfortran (actually the
whole patch was written with gfortran and the GNU Fortran argument
passing convention in mind).

Approved-by: Tom Tromey <tom@tromey.com>
1 file changed