Merge bitcoin/bitcoin#24526: build: don't install deprecated libevent headers

339b4a51f6 build: don't install deprecated libevent headers (fanquake)

Pull request description:

  We don't use the deprecated headers now, and never should do in the
  future, so there is no need for them to exist in depends.

  The headers themselves are just full of includes for the newer headers.

ACKs for top commit:
  hebasto:
    ACK 339b4a51f6

Tree-SHA512: 736fd9e3b22212da462cc05203dd253806dc59f973090357b705f2742ed4a3b8c3cc44b3173d706527f60ad93e95cf4143ec6b7db4233a489890a98f8e5c8f07

depends/packages/libevent.mk

@@ -36,5 +36,6 @@ define $(package)_stage_cmds
 endef
 
 define $(package)_postprocess_cmds
-  rm lib/*.la
+  rm lib/*.la && \
+  rm include/ev*.h
 endef