platform/surface: aggregator: Use y instead of objs in Makefile

The 'objs' is for user space tools, for the kernel modules
we should use 'y'.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210803192524.67031-1-andriy.shevchenko@linux.intel.comSigned-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/surface/aggregator/Makefile

@@ -6,12 +6,9 @@ CFLAGS_core.o = -I$(src)
 
 obj-$(CONFIG_SURFACE_AGGREGATOR) += surface_aggregator.o
 
-surface_aggregator-objs := core.o
-surface_aggregator-objs += ssh_parser.o
-surface_aggregator-objs += ssh_packet_layer.o
-surface_aggregator-objs += ssh_request_layer.o
-surface_aggregator-objs += controller.o
-
-ifeq ($(CONFIG_SURFACE_AGGREGATOR_BUS),y)
-surface_aggregator-objs += bus.o
-endif
+surface_aggregator-y := core.o
+surface_aggregator-y += ssh_parser.o
+surface_aggregator-y += ssh_packet_layer.o
+surface_aggregator-y += ssh_request_layer.o
+surface_aggregator-$(CONFIG_SURFACE_AGGREGATOR_BUS) += bus.o
+surface_aggregator-y += controller.o