syslinux: honour META_VOL_SET for boot menu

This trots along the TODO item on text branding
and hopefully helps Michael Radyuk (torabora)
with his feature request to tweak the installer's
"Install ALT Linux" label; as an example, Simply
will now offer to "Install Simply Linux".

features.in/slinux/config.mk

@@ -13,6 +13,7 @@ use/slinux: use/x11/xfce use/x11/gdm2.20
 	@$(call add,THE_LISTS,slinux/network)
 	@$(call add,THE_LISTS,slinux/xfce)
 	@$(call add,THE_LISTS,$(call tags,base l10n))
+	@$(call set,META_VOL_SET,Simply Linux)
 
 use/slinux/full: use/isohybrid use/slinux use/systemd \
 	use/firmware/wireless use/branding/complete \

features.in/syslinux/cfg.in/20install2.cfg

@@ -1,5 +1,5 @@
 label linux
-  menu label ^Install ALT Linux
+  menu label ^Install @distro@
   kernel alt0/vmlinuz
   append initrd=alt0/full.cz changedisk fastboot showopts automatic=method:cdrom ramdisk_size=@altinst_size@ vga=0x314 @bootargs@
 

features.in/syslinux/generate.mk

@@ -54,7 +54,7 @@ all: debug timeout
 	@echo $(SYSLINUX_FILES) > $(DSTDIR)/syslinux.list
 
 # integerity check
-timeout: bootargs
+timeout: distro
 	@if [ "$(SYSLINUX_TIMEOUT)" -ge 0 ] 2>/dev/null; then \
 		TIMEOUT="$(SYSLINUX_TIMEOUT)"; \
 	else \
@@ -62,6 +62,14 @@ timeout: bootargs
 	fi; \
 	sed -i "s,@timeout@,$$TIMEOUT," $(DSTDIR)/*.cfg
 
+distro: bootargs
+	@if [ -n "$(META_VOL_SET)" ]; then \
+		DISTRO="$(META_VOL_SET)"; \
+	else \
+		DISTRO="ALT Linux"; \
+	fi; \
+	sed -i "s,@distro@,$$DISTRO," $(DSTDIR)/*.cfg
+
 # pass over additional parameters, if any
 bootargs: clean
 	@if [ -n "$(STAGE2_BOOTARGS)" ]; then \