Fix bogus duplicate attribute errors for submodule functions.
PR fortran/83113
* array.c: Do not attempt to set the array spec for a submodule
function symbol (as it has already been set in the corresponding
module procedure interface).
* symbol.c: Do not reject duplicate POINTER, ALLOCATABLE, or
DIMENSION attributes in declarations of a submodule function.
* gfortran.h: Add a macro that tests for a module procedure in a
submodule.
* gfortran.dg/pr83113.f90: New test.