marvell: a3k: enable also A3720_DB_PM_WAKEUP_SRC=1

A3720_DB_PM_WAKEUP_SRC=1 enables building of additional source files
used only for Armada 3720 Development Board.

Signed-off-by: Pali Rohár <pali@kernel.org>
Change-Id: If87e5576cbc2d2c311e5fd219d957a5f18a2e12e
1 file changed