patch 9.0.0657: too many #ifdefs

Problem:    Too many #ifdefs.
Solution:   Graduate the +cmdwin feature.  Now the tiny and small builds are
            equal, drop the small build.  (Martin Tournoij, closes #11268)
diff --git a/src/Make_ami.mak b/src/Make_ami.mak
index 77ec32c..a889ebd 100644
--- a/src/Make_ami.mak
+++ b/src/Make_ami.mak
@@ -45,9 +45,9 @@
 	-DFEAT_NORMAL
 else
 
-# Vim 'small' build
+# Vim 'small' build - now an alias for 'tiny'
 ifeq ($(BUILD),small)
-CFLAGS += -DFEAT_SMALL
+CFLAGS += -DFEAT_TINY
 else
 
 # Vim 'tiny' build