Fortran: Fix assumed length chars and len inquiry [PR103716]

Fortran: Fix assumed length chars and len inquiry [PR103716]

2023-05-23  Paul Thomas  <pault@gcc.gnu.org>

gcc/fortran
	PR fortran/103716
	* resolve.cc (gfc_resolve_ref): Conversion of array_ref into an
	element should be done for all characters without a len expr,
	not just deferred lens, and for integer expressions.
	* trans-expr.cc (conv_inquiry): For len and kind inquiry refs,
	set the se string_length to NULL_TREE.

gcc/testsuite/
	PR fortran/103716
	* gfortran.dg/pr103716.f90 : New test.

(cherry picked from commit 842a432b02238361ecc601d301ac400a7f30f4fa)