aix: improve readability of os version

uname on AIX reports, e.g. 6.1 as version == 6, release == 1.
The code was previously printing this as:
  OS version: AIX 1 6
Fix so that on AIX this is now:
  OS version: AIX 6.1

src/node_report.cc

@@ -617,7 +617,11 @@ static void PrintVersionInformation(FILE* fp, Isolate* isolate) {
   // Print operating system and machine information (Unix/OSX)
   struct utsname os_info;
   if (uname(&os_info) == 0) {
+#if defined(_AIX)
+    fprintf(fp, "\nOS version: %s %s.%s\n", os_info.sysname, os_info.version, os_info.release);
+#else
     fprintf(fp, "\nOS version: %s %s %s\n", os_info.sysname, os_info.release, os_info.version);
+#endif
 #if defined(__GLIBC__)
     fprintf(fp, "(glibc: %d.%d)\n", __GLIBC__, __GLIBC_MINOR__);
 #endif