GenerateDebianControl: escape double quotes

Since it will firstly written to cmake-like config - CPackConfig.cmake,
and there we will get replaced '"' by ';' (without signel quotes), with
the following message:
  Run CPack packaging tool...
  CMake Warning (dev) in .cmake/CPackConfig.cmake:
    Syntax Warning in cmake code at

      .cmake/CPackConfig.cmake:49:65

    Argument not separated from preceding token by whitespace.
  This warning is for project developers.  Use -Wno-dev to suppress it.

  CMake Warning (dev) in .cmake/CPackConfig.cmake:
    Syntax Warning in cmake code at

      .cmake/CPackConfig.cmake:49:75

    Argument not separated from preceding token by whitespace.
  This warning is for project developers.  Use -Wno-dev to suppress it.