Same fix that went into libmariadb package with commit fd13c12.

Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>

This patch fixes the compilation issue of the upstream Cmake file.
If this patch is not applied we get the following compilation error output.

CMake Error at cmake/ConnectorName.cmake:30 (ENDMACRO):
  Flow control statements are not properly nested.
Call Stack (most recent call first):
  CMakeLists.txt:423 (INCLUDE)

The blamed cmake/ConnectorName.cmake file gets fixed with this patch.

Signed-off-by: Florian Eckert <fe@dev.tdt.de>