fix GCC 13 issues

GCC 13 removes `uint*_t` family of types from one of the common
includes so we need to explicitly include cstdint.

Change-Id: I05884edbaa38f3999fc6cd8234411d2c2c8a7429
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/msl_verify.hpp b/msl_verify.hpp
index d3015d9..e726c61 100644
--- a/msl_verify.hpp
+++ b/msl_verify.hpp
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <cstdint>
 #include <string>
 
 namespace openpower
diff --git a/ubi/serialize.hpp b/ubi/serialize.hpp
index e5fefad..eadd850 100644
--- a/ubi/serialize.hpp
+++ b/ubi/serialize.hpp
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <cstdint>
 #include <string>
 
 namespace openpower