vspace: definitions for 40-bit PA

Add VSPACE_NUM_LEVELS for 40-bit PA.

libsel4utils/sel4_arch_include/aarch64/sel4utils/sel4_arch/vspace.h

diff --git a/libsel4utils/sel4_arch_include/aarch64/sel4utils/sel4_arch/vspace.h b/libsel4utils/sel4_arch_include/aarch64/sel4utils/sel4_arch/vspace.h
index b141084..f68d018 100644
--- a/libsel4utils/sel4_arch_include/aarch64/sel4utils/sel4_arch/vspace.h
+++ b/libsel4utils/sel4_arch_include/aarch64/sel4utils/sel4_arch/vspace.h
@@ -12,17 +12,24 @@
 
 #pragma once
 
+#include <autoconf.h>
+
+
 #ifdef CONFIG_ARM_HYPERVISOR_SUPPORT
 
 #if defined(CONFIG_ARM_PA_SIZE_BITS_44)
 
 #define VSPACE_NUM_LEVELS       4
 
+#elif defined(CONFIG_ARM_PA_SIZE_BITS_40)
+
+#define VSPACE_NUM_LEVELS 3
+
 #else
 #error Unspecified PA size bits
 #endif
 
-#else
+#else /* CONFIG_ARM_HYPERVISOR_SUPPORT */
 
 #define VSPACE_NUM_LEVELS 4