Do not install header files that are not pertinent to host/build system

[zerodefect]

I'm building v17.0.1 of the ntv2 library released on March 9th, 2024.

I build the SDK as follows:

cmake -DCMAKE_BUILD_TYPE=RELWITHDEBINFO -DAJA_NTV2_SDK_BUILD_NUMBER=$AJA_NTV_PKG_RELEASE -DAJA_INSTALL_HEADERS=ON -DAJA_INSTALL_SOURCES=OFF -DAJA_INSTALL_MISC=OFF -DAJA_INSTALL_CMAKE=OFF -DAJANTV2_DISABLE_DEMOS=ON -DAJANTV2_DISABLE_TOOLS=ON -DAJANTV2_DISABLE_TESTS=ON -DAJANTV2_DISABLE_PLUGINS=ON ..
make

I noticed that Windows/Mac header files will be installed even though I am building on a Linux host and have no interest in either Mac or Windows headers. It would be preferred if the cmake scripts were more selective on which sources/headers are installed.

This is being built on Ubuntu v22.04. This has some overlap with issue #22 .