Remove C++-isms in Mir port

Related to #568.
diff --git a/src/mir_monitor.c b/src/mir_monitor.c
index f5fa0e9..b068353 100644
--- a/src/mir_monitor.c
+++ b/src/mir_monitor.c
@@ -86,7 +86,7 @@
         *ypos = monitor->mir.y;
 }
 
-void FillInRGBBitsFromPixelFormat(GLFWvidmode* mode, MirPixelFormat const pf)
+void FillInRGBBitsFromPixelFormat(GLFWvidmode* mode, const MirPixelFormat pf)
 {
     switch (pf)
     {
diff --git a/src/mir_window.c b/src/mir_window.c
index 53c21a6..3d08f6a 100644
--- a/src/mir_window.c
+++ b/src/mir_window.c
@@ -702,7 +702,7 @@
     return GL_TRUE;
 }
 
-char const* getSystemCursorName(int shape)
+const char* getSystemCursorName(int shape)
 {
     switch (shape)
     {
@@ -725,7 +725,7 @@
 
 int _glfwPlatformCreateStandardCursor(_GLFWcursor* cursor, int shape)
 {
-    char const* cursor_name = getSystemCursorName(shape);
+    const char* cursor_name = getSystemCursorName(shape);
 
     if (cursor_name)
     {