[platform][pc] add acpi_lite to the build

Probe ACPI after threads are up and running. Does nothing at the moment
except probe.

platform/pc/platform.c

@@ -25,6 +25,7 @@
 #include <string.h>
 #include <assert.h>
 #include <kernel/vm.h>
+#include <lib/acpi_lite.h>
 
 #define LOCAL_TRACE 0
 
@@ -233,6 +234,8 @@ void platform_init(void) {
 
     platform_init_keyboard(&console_input_buf);
 
+    acpi_lite_init(0);
+
     pci_init();
 
     platform_init_mmu_mappings();

platform/pc/rules.mk

@@ -8,6 +8,7 @@ CPU ?= generic
 
 MODULE_DEPS += \
     dev/bus/pci \
+    lib/acpi_lite \
     lib/bio \
     lib/cbuf