Merge bitcoin/bitcoin#31661: depends: Override default build type for libevent

d44626a depends: Override default build type for `libevent` (Hennadii Stepanov)

Pull request description:

  This PR fixes a regression for the `libevent` package introduced in bitcoin/bitcoin#29835.

  The `libevent` package defaults to the "Release" build type, which overrides our per-build-type optimization flags with `-O3`.

  To prevent this behavior, set `CMAKE_BUILD_TYPE` to "None", consistent with how other packages are handled.

ACKs for top commit:
  fanquake:
    ACK d44626a

Tree-SHA512: 77abd2e28ad8dda86eb0548d8e49ecf23bac08a2e07dc35c71db62539aa659d471c863d361534c3cf693f9945c1b4f12de7e04eef05d11f8cc5e86d6eff5242d

Author: fanquake

depends/packages/libevent.mk

@@ -10,9 +10,10 @@ $(package)_build_subdir=build
 # version as we do in releases. Due to quirks in libevents build system, this
 # is also required to enable support for ipv6. See #19375.
 define $(package)_set_vars
-  $(package)_config_opts=-DEVENT__DISABLE_BENCHMARK=ON -DEVENT__DISABLE_OPENSSL=ON
+  $(package)_config_opts=-DCMAKE_BUILD_TYPE=None -DEVENT__DISABLE_BENCHMARK=ON -DEVENT__DISABLE_OPENSSL=ON
   $(package)_config_opts+=-DEVENT__DISABLE_SAMPLES=ON -DEVENT__DISABLE_REGRESS=ON
   $(package)_config_opts+=-DEVENT__DISABLE_TESTS=ON -DEVENT__LIBRARY_TYPE=STATIC
+  $(package)_cflags += -ffile-prefix-map=$($(package)_extract_dir)=/usr
   $(package)_cppflags += -D_GNU_SOURCE
   $(package)_cppflags_mingw32=-D_WIN32_WINNT=0x0A00