RFR: 8354920: SA core file support on Linux only prints error messages when debug logging is enabled [v3]

[Daniel Jeliński]

> Currently if loading a core file fails, the diagnostic information provided on different systems is different; on MacOS we produce an error message, while on Linux we only print information if debug logging is enabled.
> 
> This PR adds some new messages on Linux to match MacOSX, and changes some of the diagnostic output to error level instead of debug. Additionally, if opening the core or the exe file fails, the system error message (strerror) is printed.
> 
> Tier1-3 testing clean.

Daniel Jeliński has updated the pull request incrementally with two additional commits since the last revision:

 - Report Pgrab errors in exception message
 - Remove odd double space

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/24722/files
  - new: https://git.openjdk.org/jdk/pull/24722/files/a9341c3a..1062e68b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24722&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24722&range=01-02

  Stats: 10 lines in 2 files changed: 2 ins; 1 del; 7 mod
  Patch: https://git.openjdk.org/jdk/pull/24722.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24722/head:pull/24722

PR: https://git.openjdk.org/jdk/pull/24722