libiio.iss.cmakein: Install msvcr120.dll if doesn't exists
libiio.iss.cmakein: Install msvcr120.dll if doesn't exists

This avoids the dependency for the Visual C++ Redistributable Packages
for Visual Studio 2013.

Signed-off-by: Michael Hennerich <38f18d03059a1bc88082b55d7ca2d9b1ebfaffe0@analog.com>

analogdevicesinc/libiio,analogdevicesinc/libiio,analogdevicesinc/libiio,analogdevicesinc/libiio