Avoid assuming a VLA access specification string contains a closing bracket (PR middl...

Avoid assuming a VLA access specification string contains a closing bracket (PR middle-end/97189).

Resolves:
PR middle-end/97189 - ICE on redeclaration of a function with VLA argument and attribute access

gcc/ChangeLog:

	PR middle-end/97189
	* attribs.c (attr_access::array_as_string): Avoid assuming a VLA
	access specification string contains a closing bracket.

gcc/c-family/ChangeLog:

	PR middle-end/97189
	* c-attribs.c (append_access_attr): Use the function declaration
	location for a warning about an attribute access argument.

gcc/testsuite/ChangeLog:

	PR middle-end/97189
	* gcc.dg/attr-access-2.c: Adjust caret location.
	* gcc.dg/Wvla-parameter-6.c: New test.
	* gcc.dg/Wvla-parameter-7.c: New test.