Add attribute @(no_sanitize_address)

The purposes of this attribute is to let procedures opt-out of being
instrumented with asan. Typically an allocator that includes 'in-band'
meta-data will be accessing poisoned values (such as tlsf).

Making asan work with these allocators becomes very challenging so
just being to ignore asan within specific allocator procedures
makes it easier to reason and removes the need to temporarily
poison and unpoison allocator data.

src/entity.cpp

@@ -258,6 +258,7 @@ struct Entity {
 			bool    is_memcpy_like             : 1;
 			bool    uses_branch_location       : 1;
 			bool    is_anonymous               : 1;
+			bool    no_sanitize_address        : 1;
 		} Procedure;
 		struct {
 			Array<Entity *> entities;