board: amarula: vyasa: Give raw space for falcon mode

RK3288 Vyasa board support falcon mode in U-Boot and SD layout start from
16MB offset for args and 17MB for uImage. So give full u-boot partition
space as 30M so-that it can occupy bigger uImage file and doesn't overlap
rootfs partition.

[Peter: use # as comment character, clarify comment wording]
Reported-by: Shyam Saini <shyam@amarulasolutions.com>
Tested-by: Shyam Saini <shyam@amarulasolutions.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Shyam saini <shyam@amarulasolutions.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

board/amarula/vyasa/genimage.cfg

@@ -12,6 +12,7 @@ image sdcard.img {
 		in-partition-table = "no"
 		image = "u-boot-dtb.img"
 		offset = 8M
+		size = 30M # falcon mode: args @ 16M args, uImage @ 17M
 	}
 
 	partition rootfs {