Merge pull request #3978 from yasuhirokimura/enable_pcre2_by_default

Enable PCRE2 by default.

CMakeLists.txt

@@ -51,7 +51,7 @@ OPTION(INSTALL_WEBUI       "Install web interface [default: ON]"
 OPTION(WANT_SYSTEMD_UNITS  "Install systemd unit files on Linux [default: OFF]" OFF)
 OPTION(ENABLE_SNOWBALL     "Enable snowball stemmer [default: ON]"              ON)
 OPTION(ENABLE_CLANG_PLUGIN "Enable clang static analysing plugin [default: OFF]" OFF)
-OPTION(ENABLE_PCRE2        "Enable pcre2 instead of pcre  [default: OFF]"         OFF)
+OPTION(ENABLE_PCRE2        "Enable pcre2 instead of pcre  [default: ON]"         ON)
 OPTION(ENABLE_JEMALLOC     "Build rspamd with jemalloc allocator  [default: OFF]" OFF)
 OPTION(ENABLE_UTILS        "Build rspamd internal utils [default: OFF]" OFF)
 OPTION(ENABLE_LIBUNWIND    "Use libunwind to print crash traces [default: OFF]" OFF)