[project] Lose the battle between tabs & spaces

I'm a tabs guy. I like tabs, it's an elegant way to represent
indentation instead of brute-forcing it. But I have to admit that the
world seems to be going towards spaces, and tooling tends not to play
nice with tabs. So here we go, changing the whole repo to spaces since
I'm getting tired of all the inconsistent formatting.

src/kernel/panic.serial/serial.h

@@ -8,14 +8,14 @@ namespace panic {
 class serial_port
 {
 public:
-	/// Constructor.
-	/// \arg port   The IO address of the serial port
-	serial_port(uint16_t port);
+    /// Constructor.
+    /// \arg port   The IO address of the serial port
+    serial_port(uint16_t port);
 
-	void write(const char *s);
+    void write(const char *s);
 
 private:
-	uint16_t m_port;
+    uint16_t m_port;
 };
 
 constexpr uint16_t COM1 = 0x03f8;