Fortran: fix parsing of type parameter inquiries of substrings [PR101735]

Handling of type parameter inquiries of substrings failed to due either
parsing issues or not following or handling reference chains properly.

	PR fortran/101735

gcc/fortran/ChangeLog:

	* expr.cc (find_inquiry_ref): If an inquiry reference applies to
	a substring, use that, and calculate substring length if needed.
	* primary.cc (extend_ref): Also handle attaching to end of
	reference chain for appending.
	(gfc_match_varspec): Discrimate between arrays of character and
	substrings of them.  If a substring is taken from a character
	component of a derived type, get the proper typespec so that
	inquiry references work correctly.
	(gfc_match_rvalue): Handle corner case where we hit a seemingly
	dangling '%' and missed an inquiry reference. Try another match.

gcc/testsuite/ChangeLog:

	* gfortran.dg/inquiry_type_ref_7.f90: New test.

(cherry picked from commit 787a8dec1acedf5561c8ee43bed0b3653fca150d)