RFR: 8284893: Fix typos in java.base

[Magnus Ihse Bursie]

I ran `codespell` on the `src/java.base` directory, and accepted those changes where it indeed discovered real typos.

(Due to false positives this can unfortunately not be run automatically) 

The majority of fixes are in comments. A handful is in strings, one in a local variable name, and a couple in parameter declarations.

Annoyingly, there are several instances of "childs" (instead of "children") in the source code, but they were not local and I dared not change them. Someone braver than me might take a stab at it, perhaps..

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Commit messages:
 - Pass #2
 - 8284893: Fix typos in java.base

Changes: https://git.openjdk.java.net/jdk/pull/8250/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8250&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8284893
  Stats: 268 lines in 180 files changed: 0 ins; 0 del; 268 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8250.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8250/head:pull/8250

PR: https://git.openjdk.java.net/jdk/pull/8250