RFR: 8251325: Miss 'L' for long value in if statement

[Calvin Cheung]

A simple one-liner fix in DCmdStart.java.

Testing:

- tier1

- all tests under open/test/jdk/jdk/jfr locally on linux-x64

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Commit messages:
 - 8251325 (initial commit)

Changes: https://git.openjdk.java.net/jdk/pull/687/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=687&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8251325
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/687.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/687/head:pull/687

PR: https://git.openjdk.java.net/jdk/pull/687