mariadb10.0.5: follow regular expression engine directory name change

Regular expresssion engine directory is changed since MariaDB 10.0.5:

regex/ ->
pcre/

fixes #2066

Reported by Kazuhiko Shiozaki. Thanks!!!

CMakeLists.txt

@@ -103,11 +103,17 @@ else()
 endif()
 find_path(MYSQL_CONFIG "${MYSQL_CONFIG}")
 
+if(EXISTS "${MYSQL_SOURCE_DIR}/pcre")
+  set(MYSQL_REGEX_INCLUDE_DIR "${MYSQL_SOURCE_DIR}/pcre")
+else()
+  set(MYSQL_REGEX_INCLUDE_DIR "${MYSQL_SOURCE_DIR}/regex")
+endif()
+
 set(MYSQL_INCLUDE_DIRS
   "${MYSQL_BUILD_DIR}/include"
   "${MYSQL_SOURCE_DIR}/sql"
   "${MYSQL_SOURCE_DIR}/include"
-  "${MYSQL_SOURCE_DIR}/regex"
+  "${MYSQL_REGEX_INCLUDE_DIR}"
   "${MYSQL_SOURCE_DIR}"
   CACHE INTERNAL "MySQL include directories")
 

configure.ac

@@ -166,7 +166,12 @@ AC_DEFUN([CONFIG_OPTION_MYSQL],[
   MYSQL_INCLUDES="$MYSQL_INCLUDES -I$ac_mysql_build_dir/include"
   MYSQL_INCLUDES="$MYSQL_INCLUDES -I$ac_mysql_source_dir/sql"
   MYSQL_INCLUDES="$MYSQL_INCLUDES -I$ac_mysql_source_dir/include"
-  MYSQL_INCLUDES="$MYSQL_INCLUDES -I$ac_mysql_source_dir/regex"
+  if test -d "$ac_mysql_source_dir/pcre"; then
+    mysql_regex_include_dir="$ac_mysql_source_dir/pcre"
+  else
+    mysql_regex_include_dir="$ac_mysql_source_dir/regex"
+  fi
+  MYSQL_INCLUDES="$MYSQL_INCLUDES -I$mysql_regex_include_dir"
   MYSQL_INCLUDES="$MYSQL_INCLUDES -I$ac_mysql_source_dir"
   MYSQL_INCLUDES="$MYSQL_INCLUDES $($ac_mysql_config --include)"
   AC_SUBST(MYSQL_INCLUDES)