vla: resolve dynamic bounds if value contents is a constant byte-sequence

vla: resolve dynamic bounds if value contents is a constant byte-sequence

A variable location might be a constant value and therefore no inferior memory
access is needed to read the content. In this case try to resolve the type
bounds.

gdb/ChangeLog:

	* findvar.c (default_read_var_value): Resolve dynamic bounds if location
	points to a constant blob.