The testcase should use dg-additional-options instead of dg-options to
not overwrite default compile flags that include path for finding
the IEEE modules.

gcc/testsuite/ChangeLog:

    * gfortran.dg/ieee/comparisons_3.F90: Use dg-additional-options
    instead of dg-options.

Tested on x86_64-linux-gnu {,-m32}.

Uros.