many: fix remaining check-pointer-deref issues

The updated parsing_hacks.h file uncovered a bunch of extra
things that the check-pointer-deref coccinelle script flags.

This commit fixes them to make the tree check-pointer-deref clean.

src/basic/unit-name.c

@@ -345,6 +345,7 @@ int unit_name_unescape(const char *f, char **ret) {
         char *t;
 
         assert(f);
+        assert(ret);
 
         r = strdup(f);
         if (!r)
@@ -547,6 +548,8 @@ int unit_name_hash_long(const char *name, char **ret) {
         le64_t h;
         size_t len;
 
+        assert(ret);
+
         if (strlen(name) < UNIT_NAME_MAX)
                 return -EMSGSIZE;