sel_logger: Fix temporary int creation

The elements of data are not ints, so using an int reference for
iteration is undefined behavior.

Change-Id: I2baedb7d7034c4db6fa16a71b5196466e4eaf10a
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/src/sel_logger.cpp b/src/sel_logger.cpp
index 83d487a..14be313 100644
--- a/src/sel_logger.cpp
+++ b/src/sel_logger.cpp
@@ -137,7 +137,7 @@
 {
     std::stringstream stream;
     stream << std::hex << std::uppercase << std::setfill('0');
-    for (const int& v : data)
+    for (int v : data)
     {
         stream << std::setw(2) << v;
     }