cmd: bmp: Split bmp commands and functions

To enable splash screen at SPL, need to compile cmd/bmp.c which also
includes bmp commands, since SPL doesn't use commands split bmp.c into
common/bmp.c which includes all bmp functions and cmd/bmp.c which only
contains bmp commands.

Add function delclaration for bmp_info in video.h.

Signed-off-by: Nikhil M Jain <n-jain1@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

include/video.h

@@ -357,4 +357,12 @@ void *video_get_u_boot_logo(void);
  */
 int bmp_display(ulong addr, int x, int y);
 
+/*
+ * bmp_info() - Show information about bmp file
+ *
+ * @addr: address of bmp file
+ * Returns: 0 if OK, else 1 if bmp image not found
+ */
+int bmp_info(ulong addr);
+
 #endif