[][openwrt][mt7988][tops][add cpu utilization fetching]

[Description]
Add cpu utilization fetching and refactor debugfs of trm and tops

Via reading debugfs file(/sys/kernel/debug/tops/trm/cpu-utilization)
to fetch each core's cpu utilization

[Release-log]
N/A

Change-Id: Iff4c965294c3054a54ba92263191856cd5c722c7
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7907085
diff --git a/package-21.02/kernel/tops/src/Makefile b/package-21.02/kernel/tops/src/Makefile
index 820ebb4..845f657 100644
--- a/package-21.02/kernel/tops/src/Makefile
+++ b/package-21.02/kernel/tops/src/Makefile
@@ -24,6 +24,7 @@
 tops-y += tdma.o
 tops-y += trm-fs.o
 tops-y += trm-mcu.o
+tops-y += trm-debugfs.o
 tops-y += trm.o
 tops-y += wdt.o