Hexagon: add screen_info for VGA_CONSOLE

Signed-off-by: Richard Kuo <rkuo@codeaurora.org>

arch/hexagon/kernel/Makefile

@@ -15,3 +15,5 @@ obj-y += vm_vectors.o
 obj-$(CONFIG_HAS_DMA) += dma.o
 
 obj-$(CONFIG_STACKTRACE) += stacktrace.o
+
+obj-$(CONFIG_VGA_CONSOLE) += screen_info.o

arch/hexagon/kernel/screen_info.c

+#include <linux/screen_info.h>
+
+struct screen_info screen_info;