reorganize pages.h header

pages.h

@@ -12,14 +12,14 @@
 #define PAGE_SIZE ((size_t)1 << PAGE_SHIFT)
 #endif
 
-static inline size_t page_align(size_t size) {
-    return align(size, PAGE_SIZE);
-}
-
 void *allocate_pages(size_t usable_size, size_t guard_size, bool unprotect, const char *name);
 void *allocate_pages_aligned(size_t usable_size, size_t alignment, size_t guard_size, const char *name);
 void deallocate_pages(void *usable, size_t usable_size, size_t guard_size);
 
+static inline size_t page_align(size_t size) {
+    return align(size, PAGE_SIZE);
+}
+
 static inline size_t hash_page(const void *p) {
     uintptr_t u = (uintptr_t)p >> PAGE_SHIFT;
     size_t sum = u;