OvmfPkg: add new shell runtime config option to documentation.

Signed-off-by: Luigi Leonardi <[email protected]>

OvmfPkg/RUNTIME_CONFIG.md

@@ -2,7 +2,7 @@
 
 Some aspects of OVMF can be configured from the host, mostly by adding
 firmware config files using the qemu command line option `-fw_cfg`.
-The official namespace prefix for edk2 is `opt/org.tianocode/` which
+The official namespace prefix for edk2 is `opt/org.tianocore/` which
 is used by most options.  Some options are elsewhere for historical
 reasons.
 
@@ -116,6 +116,16 @@ qemu-system-x86_64 -fw_cfg name=opt/org.tianocore/UninstallMemAttrProtocol,strin
 ```
 
 
+## Shell: opt/org.tianocore/EFIShellSupport
+
+This enables/disables the EFI shell.
+Default: enabled.  Usage:
+
+```
+qemu-system-x86_64 -fw_cfg name=opt/org.tianocore/EFIShellSupport,string=no
+```
+
+
 ## Platform: opt/org.tianocore/X-Cpuhp-Bugcheck-Override
 
 On some older qemu versions CPU hotplug support was broken.  OVMF