systemd-detect-virt: add page (#10723)

* systemd-detect-virt: add page

* systemd-detect-virt: "0" => "zero"

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

---------

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

pages/linux/systemd-detect-virt.md

@@ -0,0 +1,24 @@
+# systemd-detect-virt
+
+> Detect execution in a virtualized environment.
+> More information: <https://www.freedesktop.org/software/systemd/man/systemd-detect-virt.html>.
+
+- List detectable virtualization technologies:
+
+`systemd-detect-virt --list`
+
+- Detect virtualization, print the result and return a zero status code when running in a VM or a container, and a non-zero code otherwise:
+
+`systemd-detect-virt`
+
+- Silently check without printing anything:
+
+`systemd-detect-virt --quiet`
+
+- Only detect container virtualization:
+
+`systemd-detect-virt --container`
+
+- Only detect hardware virtualization:
+
+`systemd-detect-virt --vm`