stage1: Fix type mapping for c_longdouble
stage1: Fix type mapping for c_longdouble

A quick and dirty job to let the compiler use the correct size and
alignment.

andrewrk/zig,raulgrell/zig,raulgrell/zig,andrewrk/zig,raulgrell/zig,zig-lang/zig,raulgrell/zig,zig-lang/zig,raulgrell/zig,zig-lang/zig