Fix extra semicolon in DeviceWrapper
Reference issue
What does this implement/fix?
Fixes an extra semicolon after a member function in DeviceWrapper.h, which leads to the following error when compiled using -Werror,-Wextra-semi:
Eigen/src/Core/DeviceWrapper.h:69:4: error: extra ';' after member function definition [-Werror,-Wextra-semi]
};