ralloc: use rzalloc where it's necessary

No change in behavior. ralloc_size is equivalent to rzalloc_size.
That will change though.

Calls not switched to rzalloc_size:
- ralloc_vasprintf
- glsl_type::name allocation (it's filled with snprintf)
- C++ classes where valgrind didn't show uninitialized values

I switched most of non-glsl stuff to rzalloc without checking whether
it's really needed.

Reviewed-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Tested-by: Edmondo Tommasina <edmondo.tommasina@gmail.com>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

src/compiler/glsl/list.h

@@ -56,7 +56,7 @@ struct exec_node {
    struct exec_node *prev;
 
 #ifdef __cplusplus
-   DECLARE_RALLOC_CXX_OPERATORS(exec_node)
+   DECLARE_RZALLOC_CXX_OPERATORS(exec_node)
 
    exec_node() : next(NULL), prev(NULL)
    {