RFR: JDK-8266797: Fix for 8266610 breaks the build on macos

[Vyom Tewari]

this change will  include  the below headers files to Linux only. 
#include <linux/fs.h>
#include <sys/stat.h>

-------------

Commit messages:
 - fixed the indentation
 - added the additional check so that modified code get executed on linux only.
 - JDK-8266797: Fix for 8266610 breaks the build on macos

Changes: https://git.openjdk.java.net/jdk/pull/3943/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3943&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8266797
  Stats: 5 lines in 1 file changed: 3 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3943.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3943/head:pull/3943

PR: https://git.openjdk.java.net/jdk/pull/3943