Makefile: respect CONFIG_CC_OPTIMIZE_FOR_DEBUG for host tools

If CONFIG_CC_OPTIMIZE_FOR_DEBUG=y, the host tools should be built with
debug symbols and with reduced optimization.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/Makefile b/Makefile
index 93571d3..7f7dd81 100644
--- a/Makefile
+++ b/Makefile
@@ -673,6 +673,12 @@
 include/config/auto.conf: ;
 endif # $(dot-config)
 
+ifdef CONFIG_CC_OPTIMIZE_FOR_DEBUG
+KBUILD_HOSTCFLAGS   := -Wall -Wstrict-prototypes -Og -g -fomit-frame-pointer \
+		$(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
+KBUILD_HOSTCXXFLAGS := -Og -g $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
+endif
+
 #
 # Xtensa linker script cannot be preprocessed with -ansi because of
 # preprocessor operations on strings that don't make C identifiers.