Renamed internal gamma function.

src/internal.h

diff --git a/src/internal.h b/src/internal.h
index fb7fef9..ee4e92c 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -262,7 +262,7 @@
 void _glfwPlatformGetDesktopMode(GLFWvidmode* mode);
 
 // Gamma ramp
-void _glfwPlatformSaveGammaRamp(void);
+void _glfwPlatformGetGammaRamp(GLFWgammaramp* ramp);
 void _glfwPlatformSetGammaRamp(const GLFWgammaramp* ramp);
 
 // Joystick