log: correct CONFIG_LOG_TEST prerequisites

An error

	undefined reference to `do_log_test'

occurs for CONFIG_CMD_LOG=y, CONFIG_LOG_TEST=y, CONGIG_UNIT_TEST=n

Make CONFIG_UNIT_TEST a prerequisite.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
1 file changed