[librsvg/rustification] Make some arguments immutable

[Federico Mena Quintero <federico src gnome org>]

commit d11e469ffe9a5e84846f3f3973d3205fa6b6874c
Author: Federico Mena Quintero <federico gnome org>
Date:   Fri Dec 16 14:31:18 2016 -0600

    Make some arguments immutable

 rust/src/marker.rs |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/rust/src/marker.rs b/rust/src/marker.rs
index f0067ad..2426cbf 100644
--- a/rust/src/marker.rs
+++ b/rust/src/marker.rs
@@ -51,12 +51,12 @@ fn double_equals (a: f64, b: f64) -> bool {
 }
 
 fn make_degenerate (x: f64, y: f64) -> Segment {
-    Segment::Degenerate { x: x, y: y}
+    Segment::Degenerate { x: x, y: y }
 }
 
 fn make_curve (x1: f64, y1: f64,
-               mut x2: f64, mut y2: f64,
-               mut x3: f64, mut y3: f64,
+               x2: f64, y2: f64,
+               x3: f64, y3: f64,
                x4: f64, y4: f64) -> Segment {
     Segment::LineOrCurve {
         x1: x1, y1: y1,