fix docs link

Author: QuietMisdreavus

src/libstd/os/raw/uint.md

@@ -1,6 +1,6 @@
 Equivalent to C's `unsigned int` type.
 
-This type will almost always be [`u16`], but may differ on some esoteric systems. The C standard technically only requires that this type be an unsigned integer with the same size as an [`int`]; some systems define it as a [`u16`], for example.
+This type will almost always be [`u32`], but may differ on some esoteric systems. The C standard technically only requires that this type be an unsigned integer with the same size as an [`int`]; some systems define it as a [`u16`], for example.
 
 [`int`]: type.c_int.html
 [`u32`]: ../../primitive.u32.html