Kernel: Changed stat values from func to be field

- Removed virtual functions for all of the stat stuff.
This did however introduce some issues, mainly with /proc
becoming out of sync if you changed your ID. I propose we
do the linux thing and just have a stat update function
which is optional, but allows dynamic updates of stat fields
for cases such as those in uid/gid in /proc.
- Simplified the API, although still kind of annoying
it is a bit simpler.
- Moved some of the FS structure from having the FS inode inside
the in memory inode to a Serialise <-> Deserialise model where
Inodes are deserialised from disk into in memory ones and then
back into on disk ones when it comes time for syncing.
This makes it semantically better in my opinion, as it explicitly
separates disk and non-disk functionality.

kernel/kernel/Terminal/PseudoTerminal.cpp

@@ -65,8 +65,9 @@ namespace Kernel
 	PseudoTerminalMaster::PseudoTerminalMaster(BAN::UniqPtr<VirtualRange> buffer, mode_t mode, uid_t uid, gid_t gid)
 		: CharacterDevice(mode, uid, gid)
 		, m_buffer(BAN::move(buffer))
-		, m_rdev(makedev(DeviceNumber::PTSMaster, s_pts_master_minor++))
-	{ }
+	{
+		m_rdev = makedev(DeviceNumber::PTSMaster, s_pts_master_minor++);
+	}
 
 	PseudoTerminalMaster::~PseudoTerminalMaster()
 	{

kernel/kernel/Terminal/TTY.cpp

@@ -72,9 +72,9 @@ namespace Kernel
 
 	TTY::TTY(termios termios, mode_t mode, uid_t uid, gid_t gid)
 		: CharacterDevice(mode, uid, gid)
-		, m_rdev(next_tty_rdev())
 		, m_termios(termios)
 	{
+		m_rdev = next_tty_rdev();
 		m_output.buffer = MUST(ByteRingBuffer::create(PAGE_SIZE));
 	}
 
@@ -158,16 +158,15 @@ namespace Kernel
 	{
 		// FIXME: make this atomic
 		ASSERT((mode & Inode::Mode::TYPE_MASK) == 0);
-		m_inode_info.mode &= Inode::Mode::TYPE_MASK;
-		m_inode_info.mode |= mode;
+		m_mode &= Inode::Mode::TYPE_MASK;
+		m_mode |= mode;
 		return {};
 	}
 
 	BAN::ErrorOr<void> TTY::chown_impl(uid_t uid, gid_t gid)
 	{
-		// FIXME: make this atomic
-		m_inode_info.uid = uid;
-		m_inode_info.gid = gid;
+		m_uid = uid;
+		m_gid = gid;
 		return {};
 	}