mmap all the font files!

Font now uses the same in-memory format as the font files we have on disk.
This allows us to simply mmap() the font files and not use any additional
memory for them. Very cool! :^)

Hacking on this exposed a bug in file-backed VMObjects where the first client
to instantiate a VMObject for a specific inode also got to decide its size.
Since file-backed VMObjects always have the same size as the underlying file,
this made no sense, so I removed the ability to even set a size in that case.

Kernel/i386.h

@@ -120,6 +120,16 @@ public:
             sti();
     }
 
+    void temporarily_cli()
+    {
+        cli();
+    }
+
+    void temporarily_sti()
+    {
+        sti();
+    }
+
 private:
     dword m_flags;
 };