Misc: remove unintended change

src/server/database/CMakeLists.txt

@@ -8,6 +8,10 @@
 # WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
 # implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 
+if (NOT MYSQL_FOUND)
+  message(SEND_ERROR "MySQL wasn't found on your system but it's required to build the servers!")
+endif()
+
 if( USE_COREPCH )
   include_directories(${CMAKE_CURRENT_BINARY_DIR})
 endif()