config: am335x_evm: detect BeagleBone Blue using BLA

BeagleBone Blue is next grenation of boards from BeagleBoard.org, focusing
on robotics with a TI wl1835 wireless module for connectivity.

This board can be indentified by the BLAx value after A335BNLT (BBB)
in the at24 eeprom:
BLAx: [aa 55 33 ee 41 33 33 35  42 4e 4c 54 42 4c 41 30 |.U3.A335BNLTBLA2|]

http://beagleboard.org/blue
https://github.com/beagleboard/beaglebone-blue

firmware: https://github.com/beagleboard/beaglebone-black-wireless/tree/master/firmware
wl18xx mac address: /proc/device-tree/ocp/ethernet@4a100000/slave@4a100200/mac-address

Signed-off-by: Robert Nelson <robertcnelson@gmail.com>
CC: Tom Rini <trini@konsulko.com>
CC: Jason Kridner <jkridner@beagleboard.org>
CC: Will Newton <willn@resin.io>
Reviewed-by: Tom Rini <trini@konsulko.com>

board/ti/am335x/board.c

@@ -660,6 +660,10 @@ int board_late_init(void)
 		if (!strncmp(board_ti_get_rev(), "GW1", 3)) {
 			name = "BBGW";
 		}
+		/* BeagleBoard.org BeagleBone Blue */
+		if (!strncmp(board_ti_get_rev(), "BLA", 3)) {
+			name = "BBBL";
+		}
 	}
 
 	if (board_is_bbg1())

include/configs/am335x_evm.h

@@ -144,6 +144,8 @@
 			"setenv fdtfile am335x-bonegreen.dtb; fi; " \
 		"if test $board_name = BBGW; then " \
 			"setenv fdtfile am335x-bonegreen-wireless.dtb; fi; " \
+		"if test $board_name = BBBL; then " \
+			"setenv fdtfile am335x-boneblue.dtb; fi; " \
 		"if test $board_name = A33515BB; then " \
 			"setenv fdtfile am335x-evm.dtb; fi; " \
 		"if test $board_name = A335X_SK; then " \