Add a moon_version function that returns the full version string

kernel/include/config.h

@@ -3,3 +3,5 @@
 int __moon_version_major();
 int __moon_version_minor();
 const char* __moon_version_suffix();
+
+const char* moon_version();

kernel/src/config.cpp

@@ -1,4 +1,5 @@
 #include "config.h"
+#include "std/stdio.h"
 
 #define STRINGIZE(x) #x
 #define STRINGIZE_VALUE_OF(x) STRINGIZE(x)
@@ -29,3 +30,11 @@ const char* __moon_version_suffix()
     return STRINGIZE_VALUE_OF(_MOON_SUFFIX);
 #endif
 }
+
+const char* moon_version()
+{
+    static char version[64];
+    snprintf(version, sizeof(version), "%d.%d%s", __moon_version_major(), __moon_version_minor(),
+             __moon_version_suffix()); // FIXME: this string is constant each build and should only be calculated once
+    return version;
+}

kernel/src/main.cpp

@@ -32,7 +32,7 @@ extern "C" void _start()
     Init::disable_smp(); // Put all other cores except the bootstrap one in an infinite loop
     Init::early_init();
 
-    kinfoln("Starting Moon %d.%d%s", __moon_version_major(), __moon_version_minor(), __moon_version_suffix());
+    kinfoln("Starting Moon %s", moon_version());
 
     CPU::log_cpu_information();