compulab: refactor board revision handling

Move board revision handling code to a common location
for further reuse.

Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
Reviewed-by: Tom Rini <trini@ti.com>
diff --git a/board/compulab/common/Makefile b/board/compulab/common/Makefile
index 4044ac9..e343bf0 100644
--- a/board/compulab/common/Makefile
+++ b/board/compulab/common/Makefile
@@ -6,5 +6,6 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-obj-$(CONFIG_SYS_I2C) += eeprom.o
-obj-$(CONFIG_LCD) += omap3_display.o
+obj-y				+= common.o
+obj-$(CONFIG_SYS_I2C)		+= eeprom.o
+obj-$(CONFIG_LCD)		+= omap3_display.o