RFR [12] 8207748: Fix for 8202794 breaks tier1 builds

[Brian Burkhalter]

https://bugs.openjdk.java.net/browse/JDK-8207748.01

Diff included below. Build verified on Linux, macOS, and Solaris.

Thanks,

Brian

--- a/src/jdk.management/unix/native/libmanagement_ext/OperatingSystemImpl.c
+++ b/src/jdk.management/unix/native/libmanagement_ext/OperatingSystemImpl.c
@@ -75,6 +75,7 @@
 #endif /* _ALLBSD_SOURCE */
 
 #if defined(_ALLBSD_SOURCE)
+  #define dirent64 dirent
   #define readdir64 readdir
 #endif
 
@@ -422,7 +423,7 @@
     return (100);
 #else /* solaris/linux */
     DIR *dirp;
-    struct dirent* dentp;
+    struct dirent64* dentp;
     jlong fds = 0;