RFR: Removed legacy stuff from Makefile

Thu May 26 17:29:29 UTC 2022

When the old leftover files was removed the Makefile didn't work anymore since the build directory wasn't created. Fixed this and removed all handling of legacy stuff in the Makefile.

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Commit messages:
 - Removed legacy stuff from Makefile

Changes: https://git.openjdk.java.net/guide/pull/87/files
 Webrev: https://webrevs.openjdk.java.net/?repo=guide&pr=87&range=00
  Stats: 17 lines in 1 file changed: 1 ins; 14 del; 2 mod
  Patch: https://git.openjdk.java.net/guide/pull/87.diff
  Fetch: git fetch https://git.openjdk.java.net/guide pull/87/head:pull/87

PR: https://git.openjdk.java.net/guide/pull/87