ArmPkg/SmbiosMiscDxe: Support fetching System UUID

This adds an API to OemMiscLib for fetching the system UUID according to
the platform.

Signed-off-by: Nhi Pham <nhi@os.amperecomputing.com>
Reviewed-by: Rebecca Cran <rebecca@quicinc.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Leif Lindholm <quic_llindhol@quicinc.com>

ArmPkg/Include/Library/OemMiscLib.h

@@ -235,4 +235,16 @@ OemGetChassisNumPowerCords (
   VOID
   );
 
+/**
+  Fetches the system UUID.
+
+  @param[out] SystemUuid     The pointer to the buffer to store the System UUID.
+
+**/
+VOID
+EFIAPI
+OemGetSystemUuid (
+  OUT GUID  *SystemUuid
+  );
+
 #endif // OEM_MISC_LIB_H_