Refactor stack growth code to remove messy conditions

src/vm/stackgrowth.c

@@ -13,15 +13,7 @@ static bool grow_stack (const void *addr);
 bool
 try_alloc_new_page (const void *ptr, const void *esp)
 {
-  if (needs_new_page (ptr, esp))
-  {
-    if (!grow_stack (ptr))
-      return 0;
-    else
-      return 1;
-  }
-  else
-    return 0;
+  return needs_new_page (ptr, esp) && grow_stack (ptr);
 }
 
 /* Validates a given address for being a stack query and not a generic erroneous