Add Tyan S2891/S2892/S2895 as supported without special write-enables being required

Thanks Myles Watson <mylesgw@gmail.com> for the report.

Corresponding to flashrom svn r532.
Signed-off-by: Uwe Hermann <uwe@hermann-uwe.de>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>

board_enable.c

@@ -745,6 +745,9 @@ const struct board_info boards_ok[] = {
 	{ "Tyan",		"S2881", },
 	{ "Tyan",		"S2882", },
 	{ "Tyan",		"S2882-D", },
+	{ "Tyan",		"S2891", },
+	{ "Tyan",		"S2892", },
+	{ "Tyan",		"S2895", },
 	{ "Tyan",		"S3095", },
 	{ "Tyan",		"S5180", },
 	{ "Tyan",		"S5191", },