Oops. Need to escape parentheses

git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4658 3789f03b-4d11-0410-bbf8-ca57d06f2519

unix/xserver/hw/vnc/Makefile.am

@@ -72,7 +72,7 @@ pixman.h:
 	if [ ! "$$PIXMANINCDIR" = "" ]; then \
 		cat $$PIXMANINCDIR/pixman.h | sed 's/xor/c_xor/' > $(srcdir)/pixman.h; \
 	else \
-		echo Pixman include directory not set in XSERVERLIBS_CFLAGS (perhaps Pixman was not found by configure?); \
+		echo Pixman include directory not set in XSERVERLIBS_CFLAGS \(perhaps Pixman was not found by configure?\); \
 	fi
 
 fbrop.h: $(top_srcdir)/fb/fbrop.h