kernel-build: ignore runtime config options during reconfig

Don't put CC_HAS_ASM_GOTO, IS_GCC, IS_CLANG and GCC_VERSION runtime
config options into the kernel configs during reconfiguration as it
makes no sense, since these options should be set at runtime.

Fixes: FS#2588
Signed-off-by: Petr Štetiar <ynezz@true.cz>

include/kernel-build.mk

@@ -165,7 +165,9 @@ define BuildKernel
 		$(if $(findstring Darwin,$(HOST_OS)),HOST_LOADLIBES="-L$(STAGING_DIR_HOST)/lib -lncurses") \
 		YACC=$(STAGING_DIR_HOST)/bin/bison \
 		$$@
-	$(LINUX_RECONF_DIFF) $(LINUX_DIR)/.config > $(LINUX_RECONFIG_TARGET)
+	$(LINUX_RECONF_DIFF) $(LINUX_DIR)/.config | \
+		grep -vE '(CONFIG_CC_(HAS_ASM_GOTO|IS_GCC|IS_CLANG)|GCC_VERSION)=' \
+		> $(LINUX_RECONFIG_TARGET)
 
   install: $(LINUX_DIR)/.image
 	+$(MAKE) -C image compile install TARGET_BUILD=