pkg: employ better pluggability for branding

+POST_INSTALL

@@ -17,6 +17,16 @@ EOF
 cat /etc/rc.bak >> /etc/rc
 rm -f /etc/rc.bak
 
+echo "Updating /boot/loader.conf"
+touch /boot/loader.conf
+cp /boot/loader.conf /boot/loader.conf.bak
+(grep -v loader_brand /boot/loader.conf.bak; \
+    echo 'loader_brand="opnsense"') > /boot/loader.conf
+cp /boot/loader.conf /boot/loader.conf.bak
+(grep -v loader_logo /boot/loader.conf.bak; \
+    echo 'loader_logo="hourglass"') > /boot/loader.conf
+rm -f /boot/loader.conf.bak
+
 echo "Writing package version"
 mkdir -p /usr/local/opnsense/version
 if [ -f /usr/local/opnsense/version/opnsense ]; then

+PRE_DEINSTALL

@@ -6,6 +6,14 @@ cp /etc/shells /etc/shells.bak
 (grep -v /usr/local/etc/rc.initial /etc/shells.bak) > /etc/shells
 rm -f /etc/shells.bak
 
+echo "Updating /boot/loader.conf"
+touch /boot/loader.conf
+cp /boot/loader.conf /boot/loader.conf.bak
+(grep -v loader_brand /boot/loader.conf.bak) > /boot/loader.conf
+cp /boot/loader.conf /boot/loader.conf.bak
+(grep -v loader_logo /boot/loader.conf.bak) > /boot/loader.conf
+rm -f /boot/loader.conf.bak
+
 echo "Unhooking from /etc/rc"
 cp /etc/rc /etc/rc.bak
 tail -n +4 /etc/rc.bak > /etc/rc