Fortran: fix initialization of allocatable non-deferred character [PR59252]

	PR fortran/59252

gcc/fortran/ChangeLog:

	* trans-expr.cc (gfc_trans_subcomponent_assign): Initialize
	allocatable non-deferred character with NULL properly.

gcc/testsuite/ChangeLog:

	* gfortran.dg/allocatable_char_1.f90: New test.

(cherry picked from commit 818c36a85e3faec5442eb26799bfa3bba7764b36)
2 files changed