RFR: 8261300: jpackage: rewrite while(0)/while(false) to proper blocks [v2]

[Aleksey Shipilev]

> After JDK-8254702, SonarCloud instance complains about blocks like these: "Change this loop body so that it can be executed more than once."
> 
>     int initJvmlLauncherData(JvmlLauncherData* ptr) const {
>         // Store path to JLI library just behind JvmlLauncherData header.
>         char* curPtr = reinterpret_cast<char*>(ptr + 1);
>         do {
>             const size_t count = sizeof(char)
>                     * (jliLibPath.size() + 1 /* trailing zero */);
>             if (ptr) {
>                 std::memcpy(curPtr, jliLibPath.c_str(), count);
>                 ptr->jliLibPath = curPtr;
>             }
>             curPtr += count;
>         } while (false); // <---- here
> 
> There is no sense in having `while(false)` here, where the syntactic `{}` block would do. There are also other uses in the jpackage code that employ `while(0)` for this, and then they also trigger the inspection about the implicit conversion of zero int to boolean.
> 
> Additional testing:
>  - [x] Linux x86_64 (Ubuntu) tools/jpackage

Aleksey Shipilev has updated the pull request incrementally with one additional commit since the last revision:

  More cleanup in tstrings.cpp

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2454/files
  - new: https://git.openjdk.java.net/jdk/pull/2454/files/92873eee..d895c44a

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2454&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2454&range=00-01

  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2454.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2454/head:pull/2454

PR: https://git.openjdk.java.net/jdk/pull/2454