config: remove -n, -a, -s

These are removed long before our time, I don't even know what they are.
We have been rejecting them with an error message for a while too, it's
time to just remove them.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>

CHANGELOG.md

@@ -34,6 +34,7 @@
 ## Deprecated features
 
 * Setting `--shadow-exclude-reg` is now a hard error. It was deprecated almost since the start of `picom`. `--clip-shadow-above` is the better alternative. (#1254)
+* Remove command line options `-n`, `-a`, and `-s`. They were removed more than 10 years ago, it's time to finally get rid of them entirely. (#1254)
 
 ## Bug fixes
 

src/options.c

@@ -443,11 +443,6 @@ bool get_cfg(options_t *opt, int argc, char *const *argv, bool shadow_enable,
 			         "cleared under certain types of windows, you can use "
 			         "the \"full-shadow\" per window type option.");
 			break;
-		case 'n':
-		case 'a':
-		case 's':
-			log_error("-n, -a, and -s have been removed.");
-			failed = true; break;
 		// Long options
 		case 256:
 			// --config