console: use DIV_ROUND_UP

I used the clang-tidy qemu-round check to generate the fix:
https://github.com/elmarco/clang-tools-extra

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>

include/ui/console.h

diff --git a/include/ui/console.h b/include/ui/console.h
index 7262bef..8024878 100644
--- a/include/ui/console.h
+++ b/include/ui/console.h
@@ -328,7 +328,7 @@
 static inline int surface_bytes_per_pixel(DisplaySurface *s)
 {
     int bits = PIXMAN_FORMAT_BPP(s->format);
-    return (bits + 7) / 8;
+    return DIV_ROUND_UP(bits, 8);
 }
 
 static inline pixman_format_code_t surface_format(DisplaySurface *s)