Makefile: specifiy an explicite object name rather than $(BOARD).o

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/board/freescale/t1040qds/Makefile b/board/freescale/t1040qds/Makefile
index a2dba6f..93af9eb 100644
--- a/board/freescale/t1040qds/Makefile
+++ b/board/freescale/t1040qds/Makefile
@@ -4,7 +4,7 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-obj-y	+= $(BOARD).o
+obj-y	+= t1040qds.o
 obj-y	+= ddr.o
 obj-$(CONFIG_PCI)     += pci.o
 obj-y	+= law.o