[docs] "sgml" is not a valid output format

[Frédéric Delanoy]

---
 Make.rules.in | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Make.rules.in b/Make.rules.in
index fda8e81..d326247 100644
--- a/Make.rules.in
+++ b/Make.rules.in
@@ -100,7 +100,7 @@ dummy:
 
 # Manual Dependencies
 
-ALLFORMATS = html pdf sgml ps txt
+ALLFORMATS = html pdf ps txt
 
 $(ALLFORMATS:%=wineusr-guide.%): $(WINEUSR_SRCS)
 $(ALLFORMATS:%=winedev-guide.%): $(WINEDEV_SRCS)
-- 
1.8.3.4