Update cheatsheets

tldr/linux/fwupdtool

@@ -0,0 +1,22 @@
+---
+syntax: markdown
+tags: [tldr, linux]
+source: https://github.com/tldr-pages/tldr.git
+---
+# fwupdtool
+
+> Update device firmware manually or manipulate firmware files.
+> See also: `fwupdmgr`.
+> More information: <https://github.com/fwupd/fwupd/blob/main/src/fwupdtool.md>.
+
+- Display all devices detected by `fwupd`:
+
+`fwupdtool get-devices`
+
+- Install firmware from a file:
+
+`fwupdtool install {{path/to/firmware}}`
+
+- Display help:
+
+`fwupdtool {{[-h|--help]}}`