[jdk17] RFR: 8270203: Missing build dependency between jdk.jfr-gendata and buildtools-hotspot

[Erik Joelsson]

Add missing make dependency in Main.gmk.

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Commit messages:
 - JDK-8270203

Changes: https://git.openjdk.java.net/jdk17/pull/239/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17&pr=239&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8270203
  Stats: 3 lines in 1 file changed: 3 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk17/pull/239.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17 pull/239/head:pull/239

PR: https://git.openjdk.java.net/jdk17/pull/239