Fortran: character array constructor with >= 4 constant elements [PR103115]

Fortran: character array constructor with >= 4 constant elements [PR103115]

gcc/fortran/ChangeLog:

	PR fortran/103115
	* trans-array.cc (gfc_trans_array_constructor_value): If the first
	element of an array constructor is deferred-length character and
	therefore does not have an element size known at compile time, do
	not try to collect subsequent constant elements into a constructor
	for optimization.

gcc/testsuite/ChangeLog:

	PR fortran/103115
	* gfortran.dg/string_array_constructor_4.f90: New test.