Add support for SLCAN

* Adding support for SLCAN type interfaces
* Made some of the formatting more consistent

Bug: 142656299
Test: Manually with canhalctrl, canhaldump, and canhalsend
Change-Id: Ifa4c234beb75f8a0ea93bfd75555c5ed8d68dca4
diff --git a/automotive/can/1.0/tools/canhaldump.cpp b/automotive/can/1.0/tools/canhaldump.cpp
index 5713d17..99fd14a 100644
--- a/automotive/can/1.0/tools/canhaldump.cpp
+++ b/automotive/can/1.0/tools/canhaldump.cpp
@@ -49,7 +49,7 @@
         } else {
             std::cout << "   [" << message.payload.size() << "] ";
             for (const auto byte : message.payload) {
-                std::cout << " " << unsigned(byte);
+                std::cout << " " << std::setfill('0') << std::setw(2) << unsigned(byte);
             }
         }
         std::cout << std::nouppercase << std::dec << std::endl;