build: fix regression on running make kernel_menuconfig

The build system overrides HOST_LOADLIBES to add the staging dir to the
library search path. menuconfig needs -lncurses, add another override
for it.

Signed-off-by: Felix Fietkau <nbd@nbd.name>

include/kernel-build.mk

@@ -141,7 +141,7 @@ define BuildKernel
 	rm -f $(LINUX_DIR)/.config.prev
 	rm -f $(STAMP_CONFIGURED)
 	$(LINUX_RECONF_CMD) > $(LINUX_DIR)/.config
-	$(_SINGLE)$(MAKE) -C $(LINUX_DIR) $(KERNEL_MAKEOPTS) $$@
+	$(_SINGLE)$(MAKE) -C $(LINUX_DIR) $(KERNEL_MAKEOPTS) HOST_LOADLIBES="-L$(STAGING_DIR_HOST)/lib -lncurses" $$@
 	$(LINUX_RECONF_DIFF) $(LINUX_DIR)/.config > $(LINUX_RECONFIG_TARGET)
 
   install: $(LINUX_DIR)/.image