[gimp/gimp-2-10] devel-docs: update macOS support to OSX 10.10.

[Jehan <jehanp src gnome org>]

commit 6580fae7b0a9dbcff504dee47f54918e4b1de5eb
Author: Jehan <jehan girinstud io>
Date:   Wed Jun 27 16:02:30 2018 +0200

    devel-docs: update macOS support to OSX 10.10.
    
    As discussed on IRC with Mitch and Samm.
    Older versions may work, and Samm says he will build for 10.9 actually,
    but we officially only supports for 10.10.

 devel-docs/os-support.txt | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/devel-docs/os-support.txt b/devel-docs/os-support.txt
index 81057477f8..deb82cb72e 100644
--- a/devel-docs/os-support.txt
+++ b/devel-docs/os-support.txt
@@ -13,8 +13,10 @@ Minimum dependency versions can be bumped if available in Debian Testing.
 
 ### macOS
 
-Compatibility with 10.9 and over.
+Compatibility with 10.10 and over.
+64-bit only.
 
 ### Windows
 
 Windows 7 and over.
+32 and 64-bit.