external/gard: change gard manual page filename
external/gard: change gard manual page filename

This patch fixes :

	commit 6c458a036949 ("external/gard: Install gard manual page")

which did not take into account the changes from :

	commit 2e2fb4dfff5c ("Renaming to opal-gard and minus escaping")

Signed-off-by: Cédric Le Goater <2d8cace2254d4e43578d21933db015d84bcc468a@fr.ibm.com>
Signed-off-by: Stewart Smith <ec31ab75ddf977353c8f660f92ea8b23f64aef25@linux.vnet.ibm.com>

csmart/skiboot,mikey/skiboot,stewart-ibm/skiboot,shenki/skiboot,stewart-ibm/skiboot,legoater/skiboot,shenki/skiboot,qemu/skiboot,ddstreet/skiboot,mikey/skiboot,open-power/skiboot,shenki/skiboot,qemu/skiboot,mikey/skiboot,ddstreet/skiboot,ddstreet/skiboot,legoater/skiboot,open-power/skiboot,shenki/skiboot,apopple/skiboot,csmart/skiboot,open-power/skiboot,open-power/skiboot,qemu/skiboot,qemu/skiboot,apopple/skiboot,csmart/skiboot,apopple/skiboot,shenki/skiboot,open-power/skiboot,legoater/skiboot,legoater/skiboot,qemu/skiboot,legoater/skiboot,stewart-ibm/skiboot