Fixed typo (#1273)

src/dpi.rs

@@ -49,7 +49,7 @@
 //! - **macOS:** The buzzword is "retina displays", which have a DPI factor of 2.0. Otherwise, the DPI factor is 1.0.
 //! Intermediate DPI factors are never used, thus 1440p displays/etc. aren't properly supported. It's possible for any
 //! display to use that 2.0 DPI factor, given the use of the command line.
-//! - **X11:** On X11, we calcuate the DPI factor based on the millimeter dimensions provided by XRandR. This can
+//! - **X11:** On X11, we calculate the DPI factor based on the millimeter dimensions provided by XRandR. This can
 //! result in a wide range of possible values, including some interesting ones like 1.0833333333333333. This can be
 //! overridden using the `WINIT_HIDPI_FACTOR` environment variable, though that's not recommended.
 //! - **Wayland:** On Wayland, DPI factors are set per-screen by the server, and are always integers (most often 1 or 2).