Fix typo in efikeygen command

Signed-off-by: Matt Bernhard <[email protected]>

README.md

@@ -12,7 +12,7 @@ except for Linux.)
 Generate a key for use with pesign, stored on disk:
 
 ```
-efikeyen -d /etc/pki/pesign -S -TYPE -c 'CN=Your Name Key' -n 'Custom Secureboot'
+efikeygen -d /etc/pki/pesign -S -TYPE -c 'CN=Your Name Key' -n 'Custom Secureboot'
 ```
 
 (where TYPE is m if you're only signing kernel modules, and k otherwise).