patch 9.0.1994: inconsistent feature description

Problem:  inconsistent feature description
Solution: delete old mentioned feature sets small and big

The may however still be mentioned for historical reasons. e.g. The
last Amiga built version is for Vim6.2 and is still a big version.

closes: #13273

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: RestorerZ <restorer@mail2k.ru>
diff --git a/runtime/doc/usr_90.txt b/runtime/doc/usr_90.txt
index 060e0d5..781a0ff 100644
--- a/runtime/doc/usr_90.txt
+++ b/runtime/doc/usr_90.txt
@@ -173,9 +173,8 @@
 
 	--prefix={directory}		Top directory where to install Vim.
 
-	--with-features=tiny		Compile with many features disabled.
-	--with-features=small		Compile with some features disabled.
-	--with-features=big		Compile with more features enabled.
+	--with-features=tiny		Compile with some features disabled.
+	--with-features=normal		Compile with more features enabled.
 	--with-features=huge		Compile with most features enabled.
 					See |+feature-list| for which feature
 					is enabled in which case.