-BOOTOPTS=$(strip $(subst ",, $(CONFIG_X86_GRUB_BOOTOPTS)))
-ROOTPART=$(strip $(subst ",, $(CONFIG_X86_GRUB_ROOTPART)))
-#"))")) # fix vim's broken syntax highlighting
+BOOTOPTS=$(call qstrip,$(CONFIG_X86_GRUB_BOOTOPTS))
+ROOTPART=$(call qstrip,$(CONFIG_X86_GRUB_ROOTPART))