Fortran: fix passing of NULL() to assumed-rank, derived type dummy [PR104819]

Fortran: fix passing of NULL() to assumed-rank, derived type dummy [PR104819]

	PR fortran/104819

gcc/fortran/ChangeLog:

	* interface.cc (compare_parameter): For the rank check, NULL()
	inherits the rank of a provided MOLD argument.
	(gfc_compare_actual_formal): Adjust check of NULL() actual argument
	against formal to accept F2008 enhancements (allocatable dummy).
	NULL() with MOLD argument retains a pointer/allocatable attribute.
	* trans-expr.cc (conv_null_actual): Implement passing NULL() to
	derived-type dummy with pointer/allocatable attribute, and ensure
	that the actual rank is passed to an assumed-rank dummy.
	(gfc_conv_procedure_call): Use it.

gcc/testsuite/ChangeLog:

	* gfortran.dg/null_actual_7.f90: New test.