RFR: 8260264: Move common os_<unix> inline methods to a common posix source file

[Ioi Lam]

On Wed, 27 Jan 2021 19:14:52 GMT, Harold Seigel <hseigel at openjdk.org> wrote:

> Please review this fix for JDK-8260264 to move common functions from os_<unix>.inline.hpp files to os_posix.inline.hpp.  Functions ftruncate() and the two numa* functions could also be moved to os_posix.inline.hpp but would require BSD_ONLY and AIX_ONLY macros because of minor differences.
> 
> The change was tested by running Mach5 tiers 1,2 on Linux, Mac OS, and Windows, and tiers 3-5 on Linux x64.  Additionally, builds were done on Linux-s390x, Linux-ppc, Linux-arm32, and linux-x86.
> 
> Thanks, Harold

LGTM

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Marked as reviewed by iklam (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/2267