Unbreak out-of-tree builds

Signed-off-by: malc <av1474@comtv.ru>
diff --git a/Makefile.hw b/Makefile.hw
index a8c7174..87675fd 100644
--- a/Makefile.hw
+++ b/Makefile.hw
@@ -11,7 +11,7 @@
 CFLAGS += $(OS_CFLAGS) $(ARCH_CFLAGS)
 LDFLAGS += $(OS_LDFLAGS) $(ARCH_LDFLAGS)
 
-CPPFLAGS += -I. -I$(SRC_PATH) -MMD -MP -MT $@
+CPPFLAGS += -I. -I.. -I$(SRC_PATH) -MMD -MP -MT $@
 CPPFLAGS += -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE
 CPPFLAGS+=-I$(SRC_PATH)/fpu