[babl] build: remove remnants of CMYK extension

[Øyvind "pippin" Kolås <ok src gnome org>]

commit 202dd958a84b3d8a0596440d1f57b60d1e1e1292
Author: Øyvind Kolås <pippin gimp org>
Date:   Sat Nov 24 04:13:06 2018 +0100

    build: remove remnants of CMYK extension

 extensions/Makefile.am | 1 -
 1 file changed, 1 deletion(-)
---
diff --git a/extensions/Makefile.am b/extensions/Makefile.am
index 50e2a8e..a066e8d 100644
--- a/extensions/Makefile.am
+++ b/extensions/Makefile.am
@@ -54,7 +54,6 @@ gggl_table_la_SOURCES = gggl-table.c
 gggl_la_SOURCES = gggl.c
 gimp_8bit_la_SOURCES = gimp-8bit.c
 grey_la_SOURCES = grey.c
-CMYK_la_SOURCES = CMYK.c
 naive_CMYK_la_SOURCES = naive-CMYK.c
 HCY_la_SOURCES = HCY.c
 HSL_la_SOURCES = HSL.c