RFR: 8336342: Fix known X11 library locations in sysroot

[Aleksey Shipilev]

In [JDK-8257913](https://bugs.openjdk.org/browse/JDK-8257913), we added the search paths for X11 libraries, but they point explicitly to `libX11.so`. First, this is not really correct, as `x_libraries` would be added to a search path. Second, this apparently does not work for sysroots created by crosstool-ng, likely because it wants to find other libraries in the same location. Debootstrap-ed GHA seem to work because they find the X11 libraries before hitting this code, apparently.

We should just drop the `libX11.so` parts, and leave only the path.

Additional testing:
 - [x] JDK 23, 21, 17, 11 builds with the patch and crosstool-ng without problems now
 - [ ] GHA
 - [ ] A matrix of Server/Zero builds with GCC 10

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Commit messages:
 - Fix

Changes: https://git.openjdk.org/jdk/pull/20170/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20170&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8336342
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/20170.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20170/head:pull/20170

PR: https://git.openjdk.org/jdk/pull/20170