Inlining map functions causes an ICE

[pcwalton]

I added #[inline] to all the functions in map.rs and got the following error when compiling stage1/librustc:

../src/rustc/rustc.rc:1:0: 1:0 error: internal compiler error unbound function item in trans_item

[marijnh]

Oh well. I fixed this as well yesterday, but didn't push to master yet.