feat: setup initial fat reading logic

kernel/kernel.c

@@ -17,6 +17,7 @@
 #include <libc/kprintf.h>
 #include <fs/mbr.h>
 #include <fs/blockdev.h>
+#include <fs/fat.h>
 
 #define BOOTLOADER_NAME_MAX_LENGTH 64
 #define CMDLINE_MAX_LENGTH 256
@@ -149,6 +150,7 @@ void init_pci_system() {
 void init_block_devices() {
     // register drivers
     mbr_register_block_driver();
+    fat_register_block_driver();
 
     // scan
     block_dev_scan_repeat();