logread: add page (#15655)

Co-authored-by: Machiavelli <145562237+MachiavelliII@users.noreply.github.com>

pages/linux/logread.md

@@ -0,0 +1,20 @@
+# logread
+
+> Read the `logd` ring buffer log.
+> More information: <https://openwrt.org/docs/guide-user/base-system/log.essentials>.
+
+- Print the log:
+
+`logread`
+
+- Print a specified number of messages:
+
+`logread -l {{N}}`
+
+- Filter messages by (Keyword/Regular Expression):
+
+`logread -e {{pattern}}`
+
+- Print log messages as they happen:
+
+`logread -f`