Clean up MIDI menu text in readme

Removes the stray empty line and the sup tag, which didn't look so
great.

README.md

@@ -22,8 +22,6 @@ build/orca    # Run orca
 
 To choose your MIDI output device, press `F1` (or `Ctrl+D`) to open the main menu, and then select `MIDI Output...`
 
-<sup>
-
 ```
 ┌ ORCA ───────────────┐┌ PortMidi Device Selection ─────┐
 │   New               ││ > (*) #0 - Midi Through Port-0 │
@@ -40,11 +38,8 @@ To choose your MIDI output device, press `F1` (or `Ctrl+D`) to open the main men
 │                     │
 │   Clock & Timing... │
 │.....................│
-
 ```
 
-</sup>
-
 ## Prerequisites
 
 Core library: A C99 compiler (no VLAs required), plus enough libc for `malloc`, `realloc`, `free`, `memcpy`, `memset`, and `memmove`. (Also, `#pragma once` must be supported.)