[gimp/gimp-2-10] devel-docs: add "step" blending function to GGR format spec

[Ell <ell src gnome org>]

commit ed7f9454c14bb43be2fa94c966805ee67e0f759d
Author: Ell <ell_se yahoo com>
Date:   Tue Oct 30 11:02:24 2018 -0400

    devel-docs: add "step" blending function to GGR format spec
    
    (cherry picked from commit 026fe766cdf9aa49ba6d7fd751f492fe4a4debfd)

 devel-docs/ggr.txt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/devel-docs/ggr.txt b/devel-docs/ggr.txt
index 1aaa52832a..86ad15f102 100644
--- a/devel-docs/ggr.txt
+++ b/devel-docs/ggr.txt
@@ -14,7 +14,8 @@ Blending function (enum; values are:
                    1 = "curved"
                    2 = "sinusoidal"
                    3 = "spherical (increasing)"
-                   4 = "spherical (decreasing)")
+                   4 = "spherical (decreasing)"
+                   5 = "step")
 Coloring type (enum; values are:
                0 = "RGB"
                1 = "HSV CCW"