ArmPkg: Correct small typos

The 'cspell' CI test detected some small typos in ArmPkg.
Correct them.

Cc: Bret Barkelew <bret.barkelew@microsoft.com>
Cc: Sean Brogan <sean.brogan@microsoft.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Pierre Gondois <Pierre.Gondois@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>

ArmPkg/Filesystem/SemihostFs/Arm/SemihostFs.c

@@ -51,7 +51,7 @@ EFI_FILE gSemihostFsFile = {
 };
 
 //
-// Device path for semi-hosting. It contains our autogened Caller ID GUID.
+// Device path for semi-hosting. It contains our auto-generated Caller ID GUID.
 //
 typedef struct {
   VENDOR_DEVICE_PATH        Guid;