* [get_cmake_vars] add -isysroot flag independednt of crosscompiling
Even without crosscompiling it is possible to specify a VCPKG_OSX_SYSROOT or
a SDKROOT this should be popagated to autotools and meson builds as well.
* [meson] add -arch and -isysroot to linker flags in case of osx crosscompile
* [meson] avoid DEPRECATION warning about flags in the [properties] section
* [meson] don't set OSXROOT evironment varibale
* [meson] don't set MACOSX_DEPLOYMENT_TARGET environment variable
cmake appends the -mmacosx-version-min flag c/cxx flags, overriding the
value set via VCPKG_C_FLAGS. By setting the environment variable, the
VCPKG_C_FLAGS value was used for meson builds. Now the same value is
taken for both.
* [meson/make] Add CMAKE_OSX_DEPLOYMENT_TARGET to VCPKG_DETECTED_CMAKE_C_FLAGS
This is done in the same way in CMake internally
a34997af6c