board/boundarydevices: fix boot partition number in bootscript

It was previously hardcoded to use the 1st partition although the
bootpart variable was used to download kernel/dtb from any partition.

Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

board/boundarydevices/common/6x_bootscript.txt

@@ -92,14 +92,12 @@ fi
 
 setenv bootargs "${bootargs} console=${console},115200 vmalloc=400M consoleblank=0 rootwait fixrtc"
 
-bpart=1
-
 if test "sata" = "${dtype}" ; then
-	setenv bootargs "${bootargs} root=/dev/sda${bpart}" ;
+	setenv bootargs "${bootargs} root=/dev/sda${bootpart}" ;
 elif test "usb" = "${dtype}" ; then
-	setenv bootargs "${bootargs} root=/dev/sda${bpart}" ;
+	setenv bootargs "${bootargs} root=/dev/sda${bootpart}" ;
 else
-	setenv bootargs "${bootargs} root=/dev/mmcblk${disk}p${bpart}"
+	setenv bootargs "${bootargs} root=/dev/mmcblk${disk}p${bootpart}"
 fi
 
 if itest.s "x" != "x${disable_giga}" ; then