tasking: add simple base for running things in ring 3

src/mm/page_alloc.c

@@ -37,4 +37,4 @@ void free_page(void* physaddr) {
     uint32_t byte_idx = page_num / 8;
     uint32_t bit_idx = page_num % 8;
     page_bitmap[byte_idx] &= ~(1 << bit_idx); // Сбрасываем бит
-}
+}